I don\\\'t think I\\\'m bi or gay

A few nights ago I spent the night over at a friend's house. There was nothing to do, so we sat on the sofa and watched movies. While we were in the middle of one of the movies, I laid down and put my head on her leg, because she was sitting up under a blanket and I couldn't find a pillow. All of a sudden I got the sudden urge to kiss her. I'm a girl and haven't really thought about doing anything like that before. Anyway, as the movie went on the more I wanted to kiss her. All I kept thinking was "I want to kiss her so bad" then I thought about other things we could be doing and I scared the shit out of myself. I don't know what to do. I don't think I'm bi or gay, but is it normal to all of a sudden want to kiss you best friend??