This sounds a lot like anxiety to me.
You can get oral herpes from anyone - your parents, your regular partner, kissing someone in a bar. 67% of people under 50 globally have it, up to 80% overall have it. You get it from kissing mostly. It's possible to get it from giving oral sex, but far and away, it is mostly kissing.
Sex workers don't have it at any higher rates than the general public because it's already really high in the general public.
You could have it and not have symptoms because the vast majority of people who have it never get symptoms.
You don't get it from kissing breasts.
I'm not sure why you're so freaked out about it, though. If you're in the US, you can get a type specific IgG blood test, but please note that the hsv1 IgG test misses 30% of infections, and there are false positives on the hsv2 test.
Oral herpes is usually ON the lip, not inside it, and wouldn't heal within 2 days. That sounds like a canker sore, which is different.
I'm not sure your anxiety can handle a false positive.
But really, your risk here for oral herpes isn't any different than if you kissed your neighbor.