I'm really sorry this happened to you and I sure hope you make sure that it doesn't happen again. I had blackouts when I drank too, and it's the most scary thing ever.
I don't know if it was rape, and I know when I was blacked out, I was still 'functioning' - very scary. He probably took advantage of you, but may not have been aware how helpless you were. Who knows?
Do talk to a counsellor if you can.