8 days late!!

Okay, so my period is now 8 days late & I just took a test & it was negative, I asked my mom what to do & she said wait 5 days & test again... I just don't know if I'm pregnant or not & its killing me & freaking me & my boyfriend out. I have been under some stress but not anymore, so idk. Umm....this may be weird but it hurts when I have sex...like when he puts it in....It never hurt before.....