Hi there,
Unfortunately, what you’re describing sounds very familiar. We get ulcers and
thrush-like plaques on treatment. You can continue with the rinse, or tell your doctor; he can prescribe a prescription preparation called ‘magic mouthwash, which contains Nystatin, Maloxx, Benadryl, and Lydocaine. This is a swish and swallow medication that can be compounded by your local pharmacy, and nubs on contact, so at least you can get some relief.