It detects the antibodies of both HIV-1 and HIV-2. It also detects the antigen for HIV-1, but NOT for HIV-2 (which is very rare, but very real).
An antibody test at 12 weeks would certainly detect antibodies for both types and conclusively determine a person's status.
This is all relevant assuming you were UNPROTECTED FOR INTERCOURSE. If your partner used protection, then there was and is no need to test.
It is entirely up to you if you want a reassurance test. That being said I trust the experts.
Others may tell you different, but the two top HIV experts in nation Dr. Hook and Dr. Handsfield (as well as many other experts) say you do not have HIV with your negative 4 week duo. It is conclusive. Trust your test results.
The 4 week test was DUO test also called 4th generation test. Report mention that this test look for both p24 antigen and antibodies
I read your post wrong. 2 months ago would put you at around 8 weeks now? Any test taken now will give you an accurate result. However a Duo is recommended for conclusive results.
This isn't the doctors forum. They do not take questions anymore. Was the sex protected? If you used a condom there is ZERO risk and no worries. If unprotected you had a risk. Symptoms mean nothing in regards to HIV risk. Was your test at 4 weeks a DUO test? If it was a duo test you are in the clear as himself Dr. Handsfield has stated many times a duo test at 4 weeks or anytime after is 100 percent conclusive. If it was an antibody only test i'd advise to retest at 6 weeks for a more accurate result.