Suggest Treatment For Infection With Pus And Yeast In The Vagina

Hello, I have a question regarding pus in the vagina. I had my annual pelvic exam yesterday and the doctor said that I had excessive discharge and after viewing it under a microscope stated that there was an enormous amount of pus in it and some yeast was seen. She also stated that it was not bacterial vaginosis. I have had the same sexual partner for years now and was checked for STDs including gonnorhea and chlamydia approximately two years ago with negative results. I have been noticing a tenderness in my left side for around a month now that has become worse and I've been nauseated quite a bit lately with malaise. I feel pretty sure that I have an infection but I would like to know what else could be causing it. The doctor told me not to be concerned but I feel pretty bad. Thanks for your help.