Dude.. I used to be so afraid of being.. but its part of life...
If you want to meet a lot of girls your going to need to be shot down once in a while. If I go to a night club and try to talk to some women, I usually get shot down at least once... usually if i just go up and try to dance with them when they are already dancing...(i'm pretty sure thats a no-no in the world of women)
Just going up to them and saying hi, introducing yourself seems to work a lot better.
Anyways, you can't win every time... so try, try and try again... eventually you won't even care if you get shot down(unless you are really digging the chick)...
Thanks
Ryan