Hi, on March 8-14 I had my period. I have a normal 7-day period, always comes on the expected day. On March 17, I had unprotected sex. On March 18, I purchased birth control and took it, then later the same day- I got my period and it was a normal 7 day period. Today (March 31) I got prescribed birth control pills. Basically, my questions are will the plan b hormones affect my bc? and when should I take my bc? Thanks!