Pain.. and late..

I am now over a week late, my period is never late but the scary part is I’m having very sharp pains on the lower left side of my abdomen, it also hurts sometimes when I have sex in certain positions, it has been persistent for about 3 days now and hurts worse when I lay on my left side or back. I know for sure it’s not cramps I don’t know if I’m over thinking or what it could be.. any ideas?. Maybe I’m just overreacting? I also took a pregnancy test and it said negative I have no idea what to do..