Sudden light periods, no PMS symptoms- NOT pregnant. What's going on?

I am 20 years old and all of a sudden my last 2 periods were extremely light. Light as in, only a few, dark brown spots appear on my pads and then it would end in about 3 days. Before this, my periods were always extremely heavy and lasted about 5-7 days. I always used to get my period on time, every time, (1 month apart). This spotting I have right now (which I just got 2 days ago) was about 2 months late (I had my last period around the beginning of August). I always have symptoms as well, such as bloating, sore breasts, mood swings, increased appetite...but this month, absolutely no symptoms. I was just at the gynecologist 3 days ago, and everything looked fine. I got my blood test results back, and have elevated TSH and bilirubin, which I have to wait until next Thursday to see my primary doctor for.

I have not had sex, and I am certain I am not pregnant. I do not take contraceptives and never have. I have not started any new medication. I am at a healthy weight, so it is not anorexia, though I have been losing my appetite and weight recently. And obviously, since I'm 20, it has nothing to do with menopause. I am not necessarily free of stress, but I have been in far more stressful situations before and still had a normal period. So what could this be? Does the high TSH and bilirubin indicate something?

I should also mention for many years I have been extremely tired and very weak, with a fast pulse rate and very low blood pressure. This chronic sleepiness went misdiagnosed as narcolepsy, and I've been to many doctors for this and tried many medicines, none which have worked. I am certain this has a physical cause and is not a sleep disorder, but they have yet to find anything wrong.

Thank you

[umiushi]

Bump

[Bhupinder Kaur, MD]

Hello,
This could be oligomenorrhea that is infrequent or occasional very light periods. The causes could be benign tumors of pituitary gland. It could be due disease of thyroid gland like thyrotoxicosis, hormonal imbalance,  pcos (cyst in ovary) etc. Alternately you can consult a gynecologist and get it evaluated.

It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.

[umiushi]

Hi, thank you very much for the response, I was able to figure out that it is actually a thyroid disorder and I am on medicine for it now :)