I'm taking birth control pills, I take them every day at the same time. my period was 3 days early and was 5 days long. I had unprotected sex on the days I would usually be on my period, I bled a little after each time of having sex. I started the next month of pills but i've noticed that my nipples have been really sore, and constantly hard, its been 10 days since the sex. Could I be pregnant? Whats going on?