Birth control side effects?

Hi! I have been on the pill for almost two months now. I'm about a week away from finishing my second pack. Is it normal to skip a period? I'm taking the 28 day pack. Also my boobs have been really sensitive. My emotions through the roof. I am sexually active and the last time I had sex, I bled. A lot. It wasn't spotting. I didn't have any pain during sex or anything. Do you think it would be best to see a doctor? Could I possibly be pregnant? Not having a period is freaking me out. Or could all of this be side effects of the birth control?