I am 21 years old. I have been on birth control for about a year now. I have had no problems out of it. I have a period every month right on schedule. I had sex about a month and a half ago. About 3 weeks ago i started my period. It was right on schedule. I was a lil heavier than normal, but I thought nothing of it. I stopped about 5-6 days later. A few days after that I started again. It has not stopped. It was very heavy but now it is light. Could I be pregnant or have had a miscarriage and not known about it? What is wrong with me?