Hello Oral sex is a much less efficient mode of transmission of HIV infection.A number of studies have reported that the incidence of transmission of infection by the oral sex among couples discordant for HIV is extremely low;indeed one study reported NO CASES among 239 men whose only risk was receptive oral sex intercourse, WHERE 28 % knew that their partner was HIV-infected ( in your case even you din t know the status of girl while as I mentioned that 28 % were known that their partner were HIV infected ). So need no to worry in your case you are HIV free. In the mouth saliva present and saliva contains endogenous anti viral properties so oral sex is a safe way. The antibodies to HIV begin to appear 2 weeks after initial primary infection ( contract), and the period of time between initial infection and development of detectable antibodies is rarely more than 3 months. So after 2 weeks you can get test . Rapid nucleic acid amplification ( P24 pcr rna ) is the best test for confirmation for HIV infection. I didn t recommend you any test for HIV confirmation but you are in so stress , so get in above mentioned that . Hope this will help you. Good luck.