It might also be a good idea to have a vet check out the smaller dog. Due to bruising, some dog bites can look worse after a few hours than they do initially.
You also want to make absolutely sure there are no skin punctures. Even a small one will get infected, and toy breeds have thin skin. I had to PM a case once where a small puncture from a canine tooth went into the abdomen and caused peritonitis.
This is just a precaution and is not meant to scare, but it's good to be careful.