Iron-deficient anemia, stress, dieting, and a lack of certain nutrients may be the root of the problem. Also health conditions like low thyroid or lupus can cause hair to fall out and thin. I have had falling hair too, started taking biotin and have had a problem with anemia off & on and also believe stress can do it. I would recommend you get your iron level checked and don't take iron supplements unless the doctor recommends it, and also have your thyroid checked. Then if nothing else take some hair & nail supplements you can find them in drugstores and health food stores.
****Shampoos with rosemary as an ingredient help to get circulation to your scalp. You can find them in beauty product supply stores and also massage your scalp each day several times, do it while you are watching tv or whatever in your spare time.
I was anemic at your age, I was feeling a little tired one summer and my uncle suggested Geritol and it really helped, I got some color in my skin and lost weight. But only take it if you need it. You never know till you get tested for anemia and thyroid. I have never been able to grow my hair as long as my sister's did theirs, back when we were teens their hair was nearly long enough to sit on and mine fell out in cycles so it was only half as long and I'd have to get the split ends trimmed ever 6 months or so.
Well besides eating healthier. It could also be what your putting on your hair, decline products that have alcohol and use more home remedies, cut down on straighting if you do it. Use as less heat as possible.
She has some pretty good home remedies for a specific amount of things and you can always look it up just to make sure as to whether or not it would be healthy enough for your hair but it works for her and her hair looks good soo, she's mixed.
You're a young kid. Go see a doctor pronto, should not be happening now.
Find a different more cutting edge doctor. MSM supplements work for some. They're known for that. Not sure if they work good. Dermatologists are primarily for the skin. But many are real versed on hair cycles and loss too. Good luck.
I've heard rosewater can help but don't quote me on that.. >.>
Go to a doctor and have yourself checked.
Ask him if you may have a thyroid condition.