Question about STD. In this case?

Hello, I recently received oral sex from a prostitute. We did use a condom. It was only oral sex on me and nothing else. However I also kissed her body a little around the breasts. No mouth to mouth kissing. My question is what are the chances of me getting infected with some kind of STD from this? I have read that HIV is close to impossible to get infected from covered oral sex, but how about other infections? I am a bit anxious specially about me kissing her body, because there may be residues of semen that is possibly infected or maybe fluids from her breasts? Is this something to worry about? Does different STDs survive on the skin? Also this was the first (and  last) time I was with a prostitute, all my previous partners have been clean and I haven't needed to get tested before. Should I get tested for anything in this case? I would appreciate a fast response as I'm very anxious and nervous at the moment