Syn is right..nothing is going to make your hair grow out fast. I'm sure your hair looks great. Short hair on a woman can look fab! Keira Kinghtley's new short 'do is cute and Halle Berry never looks better than when she has her hair cut short.
Buy one of those hair styling mags and look at different ways to play around with your 'do while your hair grows out. Maybe you could even get a few highlights done or some other coloring to cheer yourrself up..?
If nothing like that sounds good just keep reminding yourself that your hair will grow out eventually. Don't get depressed over this...that will just make it seem like your hair is taking forever to grow out and you'll be miserable until it does.
Take care!