Diflucan?

Hi, so this might sound silly but I’m terrified of taking prescription medications. I went to the doctor this last week because I had ear and sinus pain, I was given a super strong antibiotic (augmentin) and had to stop it because I was getting stomach pain and it apparently also gave me a yeast infection and now my doctor prescribed me diflucan but warned that it may not work. Would I be better off trying to let the infection heal on its own? It feels better more every day so wondering if I should just let it heal on its own or take the pill or go get monistat I just don’t know what to do. It’s very hard for me to trust pharmaceuticals because I always seem to experience some sort of side effect or other issues are created from the medication. Sorry for the long post I’m just having a ton of anxiety about it, I’m supposed to be going on a trip with my husband next week and I just want this to go away 😢