Thanks for using Petco Pet Education Center, formerly Petcoach! These could potentially represent nodules or masses that have become ulcerated. They could also be just focal patches of dermatitis. I recommend that you have Bella evaluated by your veterinarian. This is most of the time differentiated with a test called a fine needle aspirate which is easy, cheap and pain-free. Sometimes, a biopsy is required for a diagnosis. Have Bella evaluated by your veterinarian to have this test performed to try to sort out what the diagnosis is so that the best course of action can be determined. If it does not appear to be a mass on examination, they can at least do cytology of the superficial aspect and see if infected and prescribe antibiotics for it. Keeping my fingers crossed that it is something benign!