Thanks for your concerns. Indeed, the symptoms of swelling are quite unusual for a UTI and there may be an alternative explanation, such as an allergic reaction
(allergic vulvoganitis) or a sexually transmitted disease; the best option would be to see either a family medicine doctor or gynecologist who can perform a through pelvic exam with speculum and determine further recommendations based on appearance/microbiology samples, etc.
Dr Brenes-Salazar MD
Mayo Clinic MN