Oh boy. You may have messed up your normal cycle. The thing is, you don't really get 'periods' on the pill. The pill works by preventing ovulation. What you get during the placebo week is spotting (from the cessation of hormones). You never actually ovulated. Missing pills may trigger ovulation and makes the pill ineffective for some. Normally though, missing 2 days will work out. After two days, the instructions are to talk to your doctor and not take the placebo week. You probably didn't get pregnant from this. If anything strange is occurring though, take a test.