Gay but not out and I can't tell why

I'm 17 and have accepted I'm gay for about the last 3 years or so. However, I just can't bring myself to come out. I feel like it might be embarrassing or that people will judge me. I don't know but I really do want to come out. I want to be proud of who I am but I always feel I can only be proud of that when I'm by myself. I feel like I cross a line when I make a scene out of me being gay. I'm just not too sure. I know I'm gay. I'm pretty sure people with good gaydar can tell. Maybe I'm just not too comfortable of the idea of me being gay? Once again, not too sure the reasons why. Any advice/clarification would be greatly appreciated!!!