I have been on the pill for years now. I always get my period around the same time. This month is came and went as it normally does, but about a week and a half into my next pack of pills, I got my period again. It started out very light, and two days in it turned into a normal, if not heavier period. A lot of my friends have had issues like these with different forms of birth control, but I ve never had an issue like this on the pill. Should I be concerned, or do things like this happen sometimes?