Well, goodness, doxy is taken for all kinds of reasons - acne, bronchitis and other upper respiratory infections, eye infections, gum disease, even malaria. It's a broad spectrum antibiotic, which means it's used for many, many things.
She's a CSW. You aren't entitled to her medical history. This is not a relationship where you share personal details.
Oral IS a risk for gonorrhea, chlamydia and syphilis.