How much should I get paid for this?

Hi, I'm a 16 year old girl. School's around where I live hire me to play drums in pit orchestra for their shows because i'm a lot cheaper then professional drummers. But I feel like i'm being horribly underpaid. Normally I go to four rehearsals and play in four shows and I have to take a lot of time practicing the music. The average pay I receive is 5 dollars per rehearsal (20 dollars total) and 10 dollars per show (40 dollars). What do you think I should get paid? Or is that okay?