I started taking the pill on Sunday, August 3rd but I'm supposed to get my period on the 9th. Is there any side effects I should expect? My doctor prescribed it to me on Friday, July 25th, I told her the last day I had my period and before I left the office she told me I could start taking the pill that same day or if I wanted to just wait until Sunday it was up to me. This is my first time ever taking any type of birth control and I had no idea of how this worked.