I took plan B about 12 hours after the unprotected sex. Four days later, I started having light brown discharge. That next morning, I started bleeding what seemed to be really dark brown blood, with a little bit of regular blood mixed in there when I looked at my tampon. The day after that, today, I started bleeding regularly. I'm not supposed to start my period for another 10 days, but I know Plan B kinda throws everything out of whack. So two questions: Does this mean the Plan B worked and I'm not pregnant? And, is this my period or will I bleed again in 10 days?