my boyfriend and i had unprotected sex about a week before christmas and he came inside of me. I felt weird for the next few weeks, but I thought i was just worrying myself but i took to pregnancy test about two weeks ago anyways and they were both negative. I am on seasonique, so i only get my period every three months. Then last week I got my period, and everything was normal and it stoped like last friday. Then today my stomach started hurting and i went to the bathroom and had like brown discharge and now its turned into blood, why is this happening? should i be worried?