Oral sex is considered a negligible risk which means that in theory a transmission can occur but the conditions for it to happen are so unlikely that the risk is virtually non-existent.
Unless you have had other sexual exposures in the past, I would not get tested for HIV for this act alone.
You might want to consider testing for other STIs tough (chlamydia, gonorrhea, syphilis...) as those much more common and much easier to transmit.