I had my period on 5/4/15 and ended on 5/8/15. I had unprotected sex with my boyfriend on 5/8/15, 5/9/15, 5/13/15, 5/14/15, 5/18/15, 5/19/15, 5/20/15, & 5/21/15. I had clear discharge with a hint of pink on 5/17/15 and now since 5/18/15 I have been spotting a small amount of light brown discharge every day. What could this be?