I'm 18 and a freshman at college. The past few months (november and now) my period has been very light and brown the whole week (I think my last regular period was in October). I am sexually active, but we use a condom every time, and he pulls out before he finishes so I don't think I could be pregnant. My period has never been regular, but when I get it, it usually is a pretty decent flow, nothing like this. Could this change be because I am living with 30 other girls now, and in a new environment? Or should I be worried about something else being wrong?