I May Have Made a Mistake

In 10 days I will be on stage in my first ever ballet performance. As the time nears I realize I may have made a mistake. What made me think I could do this? I am a 27 year old woman dancing at an 11 year old level with a bunch of 11 year olds and by the end of the dance I just can't seem to keep up with their energy level. Sure my breathing is fine, but my legs are like jelly. I fear I have set myself up for ultimate humiliation. On the other hand, you have all met my mother in law, so a case could be made for having already experienced ultimate humiliation at her hands.
Anyway, wish me luck, because I am terrified and I feel like an over the hill moron.