Im confusing about my doctor. he retest my gonorrhea by swap, he swap my throat then use that swap my vaginal also. is he right?

That's an interesting diagnostic approach and not done commonly. But sometimes it makes sense if cost is a concern, which might depend on your insurance status, to save you money (one test instead of two). If the result is negative, you are not infected at either site. If positive, it can't tell whether the infection is vaginal, oral or both, but treatment is the same for both.