You need to wait at least 6 to 8 weeks before doing any testing at all and yes any test can give a false positive it does happen. 3months is conclusive
-1 and HIV-2 and also looks for evidence of the p24 protein which is on the surface of the HIV virus particle.
The advantage of testing for p24 is that this indicator of HIV infection can be detected earlier than with tests that only looked for HIV antibodies. This can be any time from 4 weeks after exposure
This study reports that the test was 100% accurate if you get a negative result, and 94% accurate if you get a positive result. As with other types of HIV tests, a positive result need to be confirmed with a different test.
A negative result would only need to be confirmed with a second test if you were exposed less than 3 months ago. As with all antibody tests, the results relate to your HIV status 3 months before the test.
A case report of the DUO test taking more than 4 week to generate a positive result, emphasises the importance of confirming a negative result from any test used less than three months after the exposure risk, with a follow up test 3 months later.
The DUO test has no particluar advantages over other routine test when infection is unlikely to have been recent, because p24 is only detected for a short time after infection, and before HIV antibodies can be detected.