Hello and welcome to e health forum.
HIV transmission from oral sex with a infected person, can occur, only in case of presence of cuts, sores, ulcers in the mouth or on the genitals.
First you need to confirm the status of your sexual partner. In case you are unsure or doubt the person, then you can go ahead and get tested for HIV, to clear your doubts.
Contrary to the information provided , ELISA tests for HIV screening, are readily available in most government hospitals (Ministry of Health and Population) as well as NGOs like 'Refugees Egypt'.
Regarding to your question, testing for HIV at 3 months, post exposure, with a HIV ELISA test (4th generation) will certainly give a accurate and reliable test result and clear your doubts of HIV infection.
But the need for early testing, at 4 weeks post exposure, is advised, so that earlier detection can help in early initiation of treatment, and prevention of progression of the disease.
You can consult with your doctor or a HIV counselor, if you have any doubts or questions.