Spotting?! Trauma?! What is happening?!

So my S.O. went to pull me up off the floor and as he did I felt alot of liquid come from down there, so I bolted for the bathroom assuming I had started my period. I used some toilet paper to see and is wasn't bright red blood it was pinkish red mixed into the discharge. It was a considerable amount of it too. We had also just got down having sex as well no more than 5 minutes before. It also only stayed in my discharge for about a half hour or 4t minutes at the max. I just want an idea of what could be happening.