I had sex with my boyfriend and the condom broke so I took Plan B. I took Plan B an hour after our intercourse which was on Oct.28th. On Thursday November the 3rd, I started noticing some brown discharge coming out of my vagina and I was at first worried that I was pregnant. But then it started getting heavier and heavier and then it started turning into blood and now I'm thinking that I'm having my period early. Should I be worried about pregnancy?