I had sex on Monday, August 15. The condom broke and I got everything inside of me. I wasn't able to reach a place to get emergency contraception until Wednesday morning. On Wednesday night I started what seemed to be my period. It was bright red and lasted 24 hours and now has stopped for the most part other than a small amount when I wipe after using the restroom. Is this a sign of pregnancy or just a cause of the Plan B. Please help.