I told him I didn't want to

So one night, I remember it was valentine's day a while ago.. and I was out in a club and started talking to this guy. He was really nice to me, we got on, we danced, we kissed etc but I knew I didn't want to sleep with him that night. Anyway we decided to leave, which I was ok with and I even invited him to come back to mine. But I said he could come back for a spoon but I did not want to have sex with him and that if he'd rather not come round (coz there'd be no sex) that was completely fine and I wouldn't be offended. Anyway he said that was fine and he walked back with me. So we walked back to mine and we were chatting and I remember reminding him on the way back, several times, that there would be no sex that night (I didn't want to be a tease.. even though it's totally within my rights to say no whenever..) and he said that was fine.

Anyway we got back to mine and things started going down and the next thing I know he's having sex with me, even though I told him I didn't want to. In fact I remember one moment him say 'I feel like you're not enjoying this' to which I said 'I told you I didn't want to so no I'm not enjoying it' but he just ignored me and carried on. When it was done he got up, got dressed and left me lying there on my bed. I was in shock for a while, not quite sure what had just happened. Convinced it was my fault coz I should have shouted or shoved him off me or something, why hadn't I?! I spoke to some friends who echoed my thoughts, it was my fault, I shouldn't have invited him back in the first place.

So since then I was put off sex for many months and following this have had some very drunken encounters with guys, where on reflection I was in no position to consent (well some of these I don't even remember happening) but yeh. That's my story. Alcohol is common with all these times which makes everything a bit grey... but if I say no, if I can't say yes or if I am unconscious I DO NOT WANT TO HAVE SEX.