Ladies who have children.. Help!

My boyfriend and I are TTC... We haven't had sex in about five days. I just went to the bathroom and had a little bit of blood. Not a lot just enough to notice. I got in the shower and my boyfriend joined me. We attempted to have sex, but I felt the worst pressure in my stomach and lower back. So much pressure that hurt so bad I couldn't even keep going. He was only about an inch in. My period also isn't for another eight days. Do you think I could take a test now or should I wait until I'm supposed to start my period?