How would I overcome some shyness to be able to be in the drama club?

At my house, I'm always putting on different facial expressions. I have an 'animated face' people tell me. I make weird facial expressions sub-consciously, plus I can make facial expressions to match characters. I always put on accents, and my voice is very versatile. When I take on a character, my personality completely changes with it, and I can be clever, weird, evil, etc. without even realizing it. I never really thought of doing this before, but my mother told me today that I should join the drama club because I'm very good at acting. The thing is though, that I'm extremely shy. I've always been, and I'm so shy, that I have no friends. If I wanted to be in a play, I'd have to try out for it next year, but I can just imagine myself going up there with a red face, laughing from nervousness, with a voice barely audible. I hate that about myself. It just comes natural in social settings, but in familiar situations, I'm completely different!