I had unprotected sex, day later I get my period usually last 4-5 days, but then I kept spotting brown, well that went away. Why did that happen?.. Last week, I had unprotected sex, again, but he pulled out before ejaculating, and now (8/24/2013) I began spotting brown again & I don't get my period til the 1st days of September. Should I be worried, I know I should visit a Dr. but i want to hear opinions/answers....