7 wks pregnant, miscarriage?

My fiancé & I just had sex. We always stop at different times & check for blood. The first couple of times there was no blood but then we checked again & there was dark blood on the tip & around the head of his penis. It looked like the color of period blood. I then went to the bathroom & I kept wiping & the blood is still dark but there are  no clots & im not in any abnormal pain! We are hoping it's not a miscarriage. I wasn't bleeding all day until we had sex. We were going a little rough towards the end. We immediately stopped when we saw blood & went to the bathroom to check. What do y'all think? I'm so scared. This is our first baby.