Women Running

“Am I PMSing or Pregnant?” And other such PMS questions answered.

Don’t know if it’s PMS or pregnancy? And, how long does PMS last? There are so many questions and, thankfully, just as many answers.

Do you ever wonder why you change like Dr. Jekyll and Mr. Hyde, switching almost overnight into a carb-craving, irritated, sex-crazed stranger, during those two weeks before your period?

Maybe you didn't but during that time, PMS — aka Premenstrual Syndrome — desecrated my skin with painful acne, initiated emotional eating binges of an entire 9'in mac and cheese pan, and caused bloating and a general feeling of discomfort after every loving meal of heavy carbs.

Having PMS and then going into a long (7+ day), heavy, painful period felt like a prison sentence to solitary confinement. My PMS symptoms followed by a long period shut my whole body down — I didn’t have the energy to walk around. It took 4-hours after swallowing six ibuprofen pills just to sit up in the bed pain-free!


I thank God almost every month that I don’t have PMS anymore. And that my period is much more manageable. Not perfect. But I got early release from prison — I didn’t have to wait until menopause to enjoy my life again. (That’s a story for another time.)

But if you’re still PMSin’ here’s a collection of questions with explanations women often ask about that time of the month.

Am I pregnant? Or am I just PMSin'?

Spotting, breast tenderness, fatigue, mood swings, and appetite changes are shared experiences between pregnancy and PMS. So comparing symptoms can just confuse you.

Besides taking a pregnancy test, focusing on the patterns of your normal period symptoms will often lead you to the correct answer.

Here's basic information about the menstrual cycle that can also help your decision-making process.

  • PMS lasts for 10-17 days max because it's based on how long the corpus luteum lives.

  • The corpus luteum develops from the follicle that released your egg during ovulation. It has a short and definite lifespan of 16 days max. So, your PMS symptoms will come to an end once you start bleeding because your corpus luteum dies signaling "it's time to bleed".

  • Some PMS symptoms may last longer but two things will happen:

  1. They increase in intensity along with a bleed

  2. They decrease in intensity, disappearing altogether because you bleed.

  • You can experience light spotting near ovulation which may confuse you. But that should leave as well. And your period will come in about 2 weeks post ovulation.

  • Your period should be heavier than spotting. So, if you’re spotting before your period, it should either move into a heavier bleed if you’re only PMSin'. Or, it should go away in a few days if you're pregnant.

  • If you’re tracking your period, this may be a lot easier to determine. Although your period tracker can’t tell you when you’re ovulating since that’s not a reliable physiological indicator, it will, if you’ve done this long enough, give a great estimate of when your next period should arrive. Keep that in mind when trying to decide between pregnancy and PMS.

But you can always take a pregnancy test to determine. And that may be the easiest thing to do!

Can PMS cause back pain, dizziness, vomiting, fatigue, nausea, constipation, joint pain, and heartburn?

Yes. You can experience all of that when you have PMS.

During those 2 weeks before your period, there can be a number of things going on.

First, during the luteal phase estrogen rises and falls. The cyclic effects of estrogen can trigger night sweats, headaches, and tiredness.

Also, estrogen acts as an anti-inflammatory. But during the luteal phase, there’s a marked increase in prostaglandins, hormones that cause inflammation. They are healthy for your body but excessive amounts cause many of your PMS symptoms. Without estrogen, you feel more exposed to the effects of inflammation.

Progesterone, if you made enough from ovulation, can buffer the effects of estrogen withdrawal. It also acts as an anti-inflammatory so dampens the impact of prostaglandins. But if you don’t make enough then you’ll experience PMS.

And if you’re eating and living a pro-inflammatory life then progesterone sensitivity declines. You’ll need more progesterone than normal to eliminate PMS.

* See the question below about PMS vs PMDD for another explanation for nausea and vomiting during PMS.

Where do PMS cramps occur?

The same place period cramps occur. In the lining of your uterus. That tissue is called your myometrium.

The uterus has 3 layers. From the uterine cavity outward lies the endometrium, myometrium, and perimentrium.

Your endometrium responds to ovarian hormones. It plays the biggest role in menstruation and reproduction because it breaks down causing your bleed. And it allows the fertilized egg to implant and grows the fetus.

The myometrium is a muscle and expands when you get pregnant. If you have period cramps, this layer causes your pain. Inflammation blocks oxygen to the muscle causing the pain of cramps. Your uterus contracts normally but with increased inflammation, during your period you feel it!

The perimetrium, the outer layer, encapsulates the uterus

Can PMS cause anxiety, depression, and rage?

Yes. It may be related to a condition called Premenstrual Dysphoric Disorder or PMDD, however.

Progesterone makes allopregnanolone. It equips your nervous system to handle stress. That’s because it acts like GABA or gamma-Aminobutyric acid. This neurotransmitter acts on the brain receptors to give you a sense of calm, relaxation, and restful sleep. Allopregnanolone does the same thing.

If you have PMDD, your brain responds paradoxically to progesterone. Instead of calming you down, your brain receptors register allopregnanolone as something that incites anxiety.

Allopregnanolone also blocks the effects of GABA so it incites feelings of increased fear, low mood, unstable mood swings, and irritability.

This genetic dysfunction also makes you feel aggressive and rageful. You may even experience suicidal thoughts.

If you have difficulty with emotional control normally, PMDD magnifies your poor coping skills during the last two weeks of your menstrual cycle.


You can also suffer anxiety if you have histamine sensitivity.

Histamine is another of your inflammatory molecules. It rises in your body when you have an allergic reaction. Histamine causes hives, itchiness, redness, and even anaphylaxis shock for those who have severe allergic reactions.

But during the luteal phase, histamine levels rise because estrogen rises. Histamine and estrogen are 1st cousins and do everything together.

If you have histamine intolerance because you’re sensitive to it, then you’ll experience not only anxiety but also headaches, brain fog, nausea, and vomiting.

Drinking milk and eating fermented foods or other histamine-stimulating foods contributes to your PMS symptoms because they elevate the levels of histamine in your body.

Why do I gain weight right before my period?

The dysfunction of PMS affects your adrenal and kidney systems.

Your adrenals produce more aldosterone - a hormone that controls the level of salt in your body. Higher levels of aldosterone mean your body retains salt. Water follows salt so you retain more water. This leads to a higher volume of water in your blood. It pushes out from your blood vessels into your tissue spaces making your feet, hands, and legs swell.

So oftentimes, during PMS your weight gain is really water retention. It will dissipate as you move into your bleed.

Why do I want to eat more during my period? Or, why do I have certain cravings for salt, chocolate, or sugar?

If you crave chocolate during your period, it’s likely due to a magnesium deficiency. Magnesium supports your hypothalamus-pituitary-adrenal (HPA) axis so you manage stress better. And it resolves most of your period problems. Your body's just calling out for help.

Eat the chocolate! But, eat dark chocolate because it contains higher levels of magnesium. And it doesn’t contain milk which, as described above, contributes to histamine intolerance.


Salt cravings can be a sign of stress. Your adrenals under a great deal of stress can't produce enough aldosterone to control the levels of salt and thus the level of water in your body. It may signal a craving for salt to support retaining water in your body so your kidneys, blood vessels, and heart can work properly.


Your craving for sugar could be a few