tofu

hope your dog is ok,

have you check with your small claim count?  due to another dog owner valid the law/regulations, you need to spend so much money on medical expenses.

tofu

some paid website will able to provide the address & full name of the cell phone owner

no matter her dog is  a dangerous dog or not, her dog should be on leash on the time at the public place.  (unless you were at the unleash park).  
your dog was hurt due to her unattendant dog.  

do you have a witness?  do you have anything to prove that her dog bit your dog?