I think the daycare hurt my daughter! What should I do?

Okay, so on Friday when I got my daughter home from daycare I noticed that she had wounds all around her ankles (it looked like the upper layers of skin had been rubbed off from something wrapped around her ankles tighltly) I know that it wasn't from her shoes because she was wearing clogs that day. She told me many times this weekend that her teacher held her legs down because she wouldn't go into time out... I know that kids fib a lot (she's four)... but with her consistancy on the story I am very worried... Does anyone know what actions I would need to take to get a lawyer? I'm a single mom with not alot of money... But I don't want to this go, and I want the other parents to come forward if anything like this has happened to their children... Please Help! I don't know what to do!