This happened to me before!!!
I was definitely not afraid of the guy. I was a bit nervous, and I did have some pretty strong feelings for him at the time. Whenever we'd kiss I would tremble really bad. He was an AWESOME kisser too.
How old are you, by the way? I think age might have a little to do with it. I was 19 when this happened, but he was only the second guy I'd ever dated. I am every bit the late bloomer.