All hiv tests are accurate at 12 weeks and the DUO 4th generation test is accurate at 28 days. What was your exposure?
Yes, both viruses have the same window period. It all depend on the kind of test you go for. If you go for a normal antibody test (finger-prick) it will be accurate 3 months after the exposure. If you go for a duo combo ag/ab test, the result will be accurate 28 days after the exposure.