Yes, if you test negative at 3-months, you are negative. 3-months is now the conservative testing date as 4-6 weeks is the 99.9% (whereas it used to be 3-mo/6mo). But with advances in testing techniques, 3-Mos is definitive.
Would you like to tell that to OraSure Tech about their OraQuick Advance HIV 1/2 test that states a negative result before 3 months may not be conclusive. http://www.orasure.com/uploaded/397.pdf?138&sec=2&subsec=2 Look under, What does a negative result mean.
Personally, with a 3 month negative using the Home Access testing device, I would feel pretty good about the negative result. The test itself is as reliable as anything else out there. Some may quibble that the fact that the testing specimen is collected by the testee, in a non-clinical setting, is not ideal, but I believe that if something were wrong with the sample, Home Access would not have come up with a negative result. Instead, they would have indicated that the sample was screwed up. Make sense? The Home Access test is FDA approved, and your result is valid.