Hi! I'm an 18 year old girl, and I've had my period for 5 years. My periods were always irregular, but I never went more than 3 months without a period. My last two cycles however, have lasted almost 300 days each, meaning that I've only had one period in the last year. I'm not sexually active, so I'm not
pregnant, I haven't been under unusual stress, and I don't think I'm an abnormal weight (5'3", 102 lbs). Why is this happening and what can I do to fix it?