I agree - talk to your pharmacist. Penicillin is the #1 drug known to cause anaphylaxis. I advise my nursing students that before they give ANYBODY a dose of penicillin, they should be asking if the patient has an allergy. There's about a 10% risk of a cross-allergy to cephalosporins if you're allergic to penicillins; this is because they're based on the same chemical structure.
Pharmacists will be the most familiar with what would work for you.
There's also a possibility that it may not be an infection at all, but sadly a chronic pain problem. In about 30% of people, for reasons we don't fully understand, the pain system doesn't switch "off" once tissue healing begins. Anatomically, there's no infection, there's no visible damage, and the tissue is healing, but the nerves aren't working properly and they're generating a pain signal in the absence of tissue damage. Usually, though, it takes about 3 months for pain to be defined as "chronic". Your provider will be able to determine whether this is an infection or a chronic pain issue, and will be able to determine what medications would work for you if it is chronic pain.