Hi I am 17 years old and three weeks ago my period started. It's still here and I'm beginning to worry. I've had my period since I was 12 but this is the longest it has lasted. In the first week there were times when I'd wear the pad a few hours and it would hardly have any blood and even in the morning I would have a clean pad sometimes. But some days it would be back so I kept wearing them to I was sure it was over. Im in the third week and thought it ended today but no, still here. Sometimes it is heavy but maybe the absorption isn't good I don't know. I usually get cramps on my period but not this time. I weigh around 8 stone perhaps slightly less, but I still eat I just can't put on weight. I have acne which I'm on antibiotics for but forgot to take them for a few weeks. I'm off school today because I felt too weak. Does anyone know what's wrong with me?

Please go to a Gyne ASAP. You might be having PCOD or some other complication. Or it might be due to a hormonal imbalance.