First, I don't know what is happening with you, but you should definitely avoid sex since you have symptoms of something.
The risk of herpes is low, because it sounds like you didn't come into contact with mucus membranes, which is where she would be shedding virus from if she has it (though I question how you could not come into contact with her anus). Even so, the risk would be low for herpes from the grinding.
There is no risk for any STD from a handjob or mammary anything.
If she did not put her mouth on you unprotected, you aren't at risk for anything. If her mouth touched you briefly while putting the condom on, it's not enough to transmit anything.
So, what's causing your symptoms? You said you were tested for a UTI, and that was negative. Was that a test they did in the office and gave you results that same day?
How much caffeine and alcohol do you drink? How much water? You might be surprised at how much caffeine can affect the prostate and bladder, and cutting back can alleviate a lot of these symptoms.
Do you think any of this could be anxiety and a heightened awareness of the area?
Herpes doesn't cause vague symptoms without actual sores.
Just a note - the sex worker says that she doesn't do anything natural, but she actually does. Most sex workers don't do anything, start to finish, unprotected, including grinding. The risk is low for grinding, but there could be a risk from it. I just wanted to let you know that for the future.
So my advice is to drink more water, lay off caffeine and alcohol for a few days and see if that helps. If it doesn't, you may need to see a urologist, but I really doubt this is an STD.
Sorry I forgot to add this. When I masturbated the pain did not hurt. Also sometimes it hurt to urinate and sometimes it did not. I don't think the pain during urination was super intense. Sometimes I felt better after going to the toilet and even wiping my penis head with toilet paper.
I think you should get a prostate exam, or an ultrasound. I don't think anything you did here would cause a prostate infection, but it sounds like you may have one.
I don't see a big need for a herpes test. If it wasn't rough grinding, you didn't have a risk.
The thing with herpes tests is that there is a decent risk for a false positive. Unraveling that takes weeks, if not months, a lot of money, and it's worse if you don't live in the US, making getting a confirmatory Western Blot test very difficult.
I would suggest that you really think about an IgG test. You don't have any blisters or sores, and you didn't have penetrative sex, so there's really no reason to get the test.