So I was just diagnosed with a UTI and syphillus about a week ago. I started treatment for both which is a penicillin injection every week for the syphillus and another antibiotic for the UTI. I'm also allergic to penicillin, I got a rash from it as a child. A couple days ago my vagina started getting really itchy and it kinda burns. My question is, Is it a yeast infection from taking all of the antibiotics or an allergic reaction from the penicillin?