RLM,
As Gary and Cath say, don't take no for answer if your pain is not being adequately treated. Thrush is a fungal infection and needs to be treated immediately. It is relatively straightforward treatment when caught early. There are a variety of anti-fungal drugs that can be used including Nystatin and Diflucan.

If you don't get satisfaction, consider switching doctors, and get a second opinion in the process. I found that sometimes I had to be obnoxiously pushy to get what I considered appropriate treatment. Seems to be part of the journey. Good luck, Sheldon