Brief Answer:
The most reliable test would be a blood test

Detailed Answer:
Hi,
Thanks for writing to us.
As six months have already elapsed, the most reliable test in your case would be a blood test to detect antibodies against HIV in body. This is done by ELISA ( enzyme-linked immunosorbent assay) for HIV. If ELISA for HIV comes positive the same is confirmed again by western blot.

Usually ELISA for HIV takes a day to three days. If results are positive, another day is required to confirm the same by western blot. So roughly a lab may require a single day to four days for result confirmation.

Hope that answered your query. Should there be any doubt, please write back.

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Brief Answer:
rapid ELISA test can be done but its less reliable

Detailed Answer:
Hi,
Thanks for writing back.
1) Rapid test can be done for HIV detection. If one test is positive, second test is also done for confirmation and accuracy. Saliva sample can be used for same. However blood sample and ELISA for HIV detecting antibody is more accurate

2) You can visit any of the medical colleges or government hospital nearby in your area. Hospital attached to a medical college have a fully functional HIV clinic with counsellors and doctors.
As almost six months have passed, a single day would not increase the risk so go with a more accurate blood test instead of going with rapid ones.

Please do not panic or stress yourself. Even if a person has a single unprotected contact with HIV positive person, the chances of getting the infection are very low. So if you had a single unprotected intercourse with a girl who could have been HIV positive, chances are you might not be having the disease.

Hope that helped

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