Suggest Treatment For Pustules On Right Tonsil And Pain In Throat

well, I have a white spot it looks like pus pocket on right tonsil, I went to dr about 2 months ago at that time mt throat hurt. he checked for strep which it wasn't ,but he said it needed to be treated with antibiotic so I took them. I still have the spot and have noticed white looks like ulcer in my throat. what could this be?it doesn't hurt. the white spot is not pus I have hit with q tip as well as my finger it will not come off.