Caught Off Guard

I was out at a bar with my friend last night when I met this guy. We clicked immediately and ended up back at his place. One minute we were talking, next thing I know he's pulling down my panties and his hands are all over me. He went down on me without any warning, but it felt so good I couldn't stop him. Afterward, I feel confused, was this really just a spur-of-the-moment thing for both of us? Is this normal?