Receiving oral sex is not a risk of getting HIV. But it exposes you to syphilis, gonorrhea and herpes. You should test for all those ones, as sometimes they don't show any symptom at all.
-3 weeks after the exposure, you can test for gonorrhea.
-6 weeks after the exposure, you can test for syphilis, but if you get it negative, it would be good to re-test after 3 months, as there are people that take longer to show a positive result.
-3 months after the exposure you can test for herpes.
Even with that exposure, the risk is really low, but is always good to test if we don't know the person we have had the sexual intercourse with.
There are also special condoms for oral sex, thinner than the normal ones and sometimes with flavor. Maybe it's an option for the future.
All the best.
DragonPulse.