Hello!
I had gone through your query and understand your concern.
It is known that the chance of getting infected during an unprotected anal sex is very high (higher than during vaginal sex).
It is necessary you get tested for
HIV infection.
Most HIV tests are antibody tests that measure the
antibodies against HIV.It take some time for the immune system to produce enough antibodies for the antibody test to detect.This time is called window period and can last up to 3-6 months.
So if you do this test you can do it after 1 month of possible HIV exposure and if the result is negative you have to repeat it after 3 months and again after 6 months.If after 6 months the test result negative then you are not infected.(so HIV negative).
Another test is PCR test(Polymerase chain reaction test) is done to test the actual virus.This test is used for testing the
viral load of HIV-positive people.It is done 2-3 weeks after infection.
This test can give a conclusive result much sooner than antibody test but it is expensive.
I suggest to get tested right away.
Hope my answer has helped.
Take care.
Dr.Rovena