There is a risk for gonorrhea, chlamydia, syphilis, and genital herpes type 1, if you don't already have oral herpes type 1.
The risk is much lower than vaginal or anal sex.
You can test for gonorrhea and chlamydia at 7 days, and syphilis at 6 weeks.
You can get a test for hsv1, but it's not terribly accurate - it misses 30% of infections, and won't tell you if it's an oral or genital infection. It will only tell you if you have antibodies for it. It's also not easy to get in a lot of countries. Unless you get sores, I wouldn't bother. Sores typically appear within 2-20 days.
Keep in mind that 67% of the global population has hsv1, and a sex worker isn't any more likely to have oral hsv1 than anyone else.