Have you been diagnosed with herpes?
Is this a continuation of your risk questions from your encounter of unprotected oral sex?
If that's the case, then your risk for herpes would be genital hsv1. If you already have hsv1 orally, you can't get it again genitally.
I'd suggest getting a type specific IgG blood test from your doctor if you are able to get one, and can't remember ever having a cold sore or fever blister. (90% of those with hsv1 never get any symptoms, and about half the adult population has hsv1.) If you are in Canada, the UK, and some other areas, it's not easy to get this test.
If you only have itching and burning, that can be many, many things, including being hyper-aware of the area since you are concerned. If it's constant, and you haven't had an outbreak, that's not herpes.
Have you been tested for gonorrhea and NGU? Those are both a risk from receiving unprotected oral.