Please, someone help me. I did 2 times 4th gen. HIV Ag/Ab lab test, after 9 and 15 weeks from exposure (after 2 & 3 months). Can I be sure, I don’t have HIV? Or should I test again after 6 months?

 Fourth-generation HIV tests are highly accurate and reliable, particularly when taken after the recommended window period. The window period is the time it takes for the body to produce enough antibodies and antigens for the test to detect HIV. For fourth-generation tests, this window period is usually around 2-6 weeks after exposure.

Given that you've taken two tests after 9 and 15 weeks respectively, which is well beyond the window period, and both tests have come back negative, it's very likely that you do not have HIV. However, it's always a good idea to consult with a healthcare professional for personalized advice.

Regarding the need for further testing after 6 months, guidelines vary depending on the healthcare provider and the specific circumstances of the individual. Some experts recommend retesting at 3 months after exposure for conclusive results, while others suggest testing at 6 months for absolute certainty. It's best to discuss this with a healthcare provider who can offer guidance tailored to your situation.