1) if u r worried about hsv, then go get a hsv test
2) no antibiotics does not work for virus. Antivirals are prescribed instead
Get tested for Mycoplasma Genitalium.
It’s not likely to be hsv I wouldn’t get tested for it. First see if you can find out if the girl has it if you can put this into perspective transmission rates for hsv2 from female to male for couples who have sex unprotected twice a week is 4% so it’s highly unlikely you got it from having sex 3 times. If the girl even has it and knows about it she could be taking antivirals and that would reduce the chances by half
How bad is your pain? The doctors have answered many questions pertaining to herpetic urethritis on this site, stating that if you had it, it'd be one of the most painful things you've ever experienced. Also, herpetic urethritis rarely occurs without obvious sores/lesions on your genitals.