I think she had got injured and in need of antibiotics and other treatment. Now its important that you will take him for checked by doctor see what they suggest. Pets can't express there problems, so its very important to have a regular check of them, that there will be no cuts, rashes, or any other kind of problem in there skin or any other part of body, and if they got any injury then provide them first aid so that they can get relaxed at that time and then within time take them to a good doctor.... Pets care is very important...