You know, most CSW's are trying to protect THEMSELVES from people such as you that frequent them. They have their own vested interest in safety for themselves. Keep that in mind. You are a csw customer making you as much a risk to them as they are to you.
With that sad, you are worrying for nothing. Oral sex is NOT a risk for HIV. The only risks for HIV transmission are to have unprotected vaginal or anal sex or to share IV needles to inject drugs. That's it. Air and saliva inactivate the virus. To date, not a single person has ever been evidenced or documented to have gotten HIV from oral sex. You will not be the first.
And since it was NO RISK, all your questions are irrelevant. You didn't need to test and don't need to going forward. No symptoms have anything to do with this episode since it was no risk. and no, cortisone has nothing to do with hiv risk.