Negative test results...

Do people on here often get negative test results for thrush?

I've just gotten a negative test result for oral thrush (in fact I was told that the flora was normal, even though I've got distinct white/yellow patches on my tongue, bumps and a slightly sore throat all the time) and i really have no idea how treat it. A week of fluconazole had no effect after the first couple of days, same for nystatin.

Any ideas?