I'm posting this here because I don't know where to actually post it. My periods are regular and have been since I started taking the pill back in July. I've also been taking my Topamax for migraines (can cause birth control to be ineffective). I've had unprotected sex recently and my period isn't due for another nine or ten days, and I'm bleeding. Not extremely heavily, but enough to wear a liner or pad. I feel like it's too early to get a positive test though.