What Causes White Spots On Tongue And Cheeks?

Hi, i have a small unscrape white spot cover my entire tongue and white line in side my cheeks that comes up to my lips. i have HIV rapid test at 4 months after my last low risk exposure which is negative,but still the white tongue and cheeks not clear, i used Nystatin and fluconazole still to change, pls. is this the sign of HIV and should i have another test at six months, and what is the possibility of test result.