So I had sex for the first time 2 weeks ago. After the third time having sex, I started bleeding, like a full on period. This worries me because I am in my third month of taking birth control pills and I wasn't due for my placebo pills for another week. I bled for like a week, and I took my placebo pill yesterday. I was supposed to get my period yesterday but I'm only brown and spotting. Should I be concerned? I don't know what I should do... I'm thinking of buying the plan b just in case.