Yest infection

Ok ladies I'm in bad shape. My vagina burns so bad I can't pee! It feels like it's super dry in between a itching and burning feeling. My vagina kind burns more when I sit down. I think it's from this antibiotic I started on Friday because it started Saturday. At work I was given Diflucan and input a vaginal cream on but still no relief. How long does it take. Do you think it's a yeast infection?