Can't remember having sex

Went out with some friends on Tuesday night, and we ended up at a house party at a students house. I know a couple of the guys from uni. To cut a long story short, my friend went upstairs with two guys. Some guy who i did have my eye on, started kissing me. I remember him locking the door and the lights went out. He told me he had just broke up with his girlfriend (lies). I only remember him saying should I get a condom and I was crying over my ex (embarrassing). He told my friend we did sleep together but I just can't remember it all happening. He's blocked me on all social media, obviously because he is in a relationship which i found out the morning after. I feel ashamed mainly. Has anyone been in a situation like this before?