Take a pain relief tablet, now! Maybe sit in a cooling bath with bicarbonate of soda in . Pat the area, don't rub.
If you have severe thrush you need appropriate treatment.
Canestan burned so badly that I needed to sit in a cool bath for hours. One shouldn't self diagnose thrush unless it's 'common' occurrence. Thrush thrives on sugars, which is why the mouth can be affected too.
Get some LIVE yoghurt. Greek is very good. Eaten and applied. It helps to cleanse the digestive tract from top to bottom - several large spoonfuls daily for 5 days. Also lay on a large towel and put a good dollop as high into the vagina as possible ...... then doze. A friend uses a tampon coated so that she can ease it high into the vagina. It worked for me several years ago. My first attack of thrush was after I had stopped The Pill ........ the 2nd after emergency surgery and I was advised about the LIVE yoghurt trick then. [Keep the two pots separate though

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I would stop the VA treatment, you may be sensitive to fillers/coatings or even the product. I haven't had problems with it's sister,
Ovestin which is inserted via applicator from a tube so less coatings. Some ladies find that 'yes' and 'sylc' products R useful.