I also don't think you need to specifically state you had sex with an escort. You can tell her that you have had sex before, but that is about all of the explanation someone owes a future partner, that plus being entirely certain of your health status and the possibility of passing along an unpleasant surprise. Any person in the world who has sex should continuously be sure of their status regarding sexually transmitted disease. If you feel you have been exposed to HPV, talk to your doctor. If this fear is imaginary, let it be a useful prompt to get the HPV vaccine. Every gentleman should, for the sake of the ladies in his life.
I think, there is no need to narrate the history and do not ask her about the past. However both of you must get clean report about your health...