My period is seven days late, had unprotected sex a couple days before. We were intimate today, then just now, a few hours later, there was blood. Normally when I start my period it's dark, this was not dark and it wasn't as runny as usual. I don't know if it's implantation bleeding, maybe bleeding from our time today, or my period. I don't know if anyone has any opinions or thoughts, but I'll find out more tomorrow I believe. How long does implantation bleeding last? Should I still take a pregnancy test tomorrow?