I'm 17, I'm sexually active, but I'm also on birth control. I've taken 6 tests in the past two months and they've all said negative, not to mention that I've gotten my period every month, so I don't believe I'm pregnant. I'm experiencing really sore nipples though, and I'm worried about it. Could there be a chance I am? Because I've been told that that's a main symptom. Please help!