Suggest Treatment For Missed Periods With Mood Swings

I haven't had my period in 7 months, since of August of 2010. I am wondering if it s alright not to have your period, personally it disgusts me.. The whole summer of 2010, I would exercise for about three to four hours, but my period was still ongoing. When school started, I was pretty emotional, and I wouldn t understand why, I would cry almost everyday. I had stopped working out completely, and still waited for my period - and again, I was very angry and depressed.... I had cramps all the time, and months went by without anything. After winter break, in January I started working out again, during this month I had black blood for about three to four days, and anal bleeding at different times. This whole stage i m noticing I look weak and feel very weak, I look tired, it s been hard to fall asleep, and I feel as if my face is looking much older than it should be. I got blood tests today and am waiting for results if I may have a thyroid problem, but I have before gotten the thyroid test before, and it was fine. I m wondering if i can just allow my body not to have monthly periods, or should i take medication? Will not having periods effect any sort of growth, aging faster, early menopause, cancer, etc.??? Will this effect any future problems with sex or wanting kids? I am only at the age of 16...