Guys...Have you ever been shy and froze up when a pretty girl tried to talk to you?

I'm a girl, I feel that I'm very confident when I talk to people and I don't think I'm ugly either... I'm very nice, sweet, bubbly, open, and when I dress up I consider myself pretty... Problem is I approached this one guy and striked him up in conversation and it was pretty obvious that I was trying to get to know him and introduce myself b/c I was interested in him, so I tried to get to know him but he gave me the strangest and most coldest and detached reaction that I was completely mindblown and felt so embarred and put down afterwards... Do you know how bad it was? It was SO bad that his WHOLE BODY was angled away from me and he didnt even look me in the face 3/5th of the time...It made me feel so bad that anyone had the nerve to act so repulsed by me. Never before have I been blown off like that. Boys...I need some help and advice in coping =(