sex and yeast infection

okay so i had some kind of vaginal infection, my doctor didn't really test me or anything she just gave me the one tablet for a yeast infection. i took that pill on wednesday, and all the itching pretty much went away completely yesterday. so today i thought i would be okay to have sex. WORST PAIN IVE EVER BEEN IN. i cried for so long. and i have never been in pain from sex, not even the first time. so should i have waited longer? could the yeast infection still be there? i'm going to wait another week until i have sex again, if it still hurts then should i go back to my doctor?