Ballet performance today? I have good confidence, but I'm shaky when in poses?

This is my first year of dance and I've advanced a lot, but now it's performance time, and at the dress rehearsal I did fine, but whenever I was in a pose, I'd shake a lot--shaking to the point of being too unbalanced to worry about turnout. I used to do figure skating, and I remember that performances and competitions weren't bad at all; it was just the time leading up to getting out in front of everyone that was awful. I know in general, ballet and figure skating are very similar, but I can already tell that they're not too similar when it comes to performances. So, any advice? Particularly to help with the unsteadiness?