help!!

So my period is 8 days late, I've had cramps that I thought were signs my period is coming and clear discharge.. and the past two days my boobs have been super sore.. every time I've had sex with my boyfriend, we used a condom then afterwards made sure it was still okay and didn't rip, etc. I took a pregnancy test and it said negative. So what could be going on?? Any help is appreciated since I can't really talk to my family about my sex life.