You are not a gay but you feel shy when you are in front of a girl what to do?

Of course you're not gay... gay guys don't get shy in front of girls...

(For those offended: I was making light of the stereotype.)

Practically all nice guys get shy in front of girls... (it's because you're nervous and you want her to like you) but most girls aren't particularly engendered to shy guys, they like confidence.

So here's what you do... talk to her like she's a guy. It may seem counterproductive but if you think of her as a guy your attitude changes and it's a lot easier for you to be 'comfortable' around her.