hi,im a young 19 year old.I had my period on april 11, 2009 .right after my period was done on the 16th i started having unprotected sex with my boyfriend.by the time my period was due on may 11,2009 i started a very very light pink discharge so light that when i wipe you couldnt even see it. so that continue for about 3 days and then the rest was a very light brown discharge and that also continued for 2 days.im late for my period now 21 days. i have been experiencing headaches, moody ,eatting more than often,a bit of sore breast,and been really tired.i had took a pregnacy test at home 7 day after i was due for my period but negative. ps between all this time i been having unprotected sex.