You didn't have a low risk exposure. You had no risk so there is no point in testing.
HIV is instantly inactivated in air and also instantly in saliva so it is effectively dead and can't infect from oral or kissing so you didn't need to test. Do not waste any more time or money testing for a HIV disease you can't have.
Only sex risks are unprotected penetrating vaginal or anal and non sex risk is injecting from a shared needle. No one in 40 year HIV history got it from oral sex, so after 40 years the above science is very well established, and nothing you can add will make your situation a risk.