Question 3 first, because it is central to your other questions: You are right. The higher the risk of HIV exposure, the more important it is to be tested later rather than earlier. Although your negative result 8 weeks after possible exposure is highly (probably almost 99%) reliable, because you are in a country where heterosexual transmission of HIV is very common, you should be tested again at 3 months. (See other threads on "time to positive HIV test" for information about why the level of risk influences this.)
1 and 2) Having said that, the test result remains infinitely more reliable than symptoms as an indicator of HIV infection. "Furry" (or coated) tongue has lots of potential causes in addition to HIV. And yes, tongue abnormalities are much more likely with late than early HIV infection. 4) You aren't being an idiot by any means, but your symptoms do not suggest HIV.
5) Other comments? First, your 8 week test result makes it extremely unlikely you acquired HIV during the exposure you describe--but get tested again in another month. Second, for goodness' sake, what the heck are you doing having unprotected sex (assuming this was a non-monogamous context) in South Africa??!! Don't do it again.
Best wishes. Get (and stay) safe. HHH, MD
my mother is a dental hygenist and thats why i am answering your question. she has a book with pictures of different oral problems and hairy tongue was one of them so i found a website that talks about this that you can take a look at.http://www.emedicine.com/derm/topic639.htm
pay attention to section 3 Clinical, while it is seen in patients with HIV it is not a symptom of HIV. it is mostly seen in people who drink a lot of tea or coffee or use tobacco products. also can be in result to poor oral hygiene
I guess down there you should make sure the tests are checking for HIV-1 and HIV-2, I would be surprised if they weren't.
I wonder why it is so prevalent down there, and like you said with black Africans particularly. I don't see how the 1/1000 or 1/2000 average risk for heterosexual contact could apply in that region, it's not enough to sustain that kind of infection percentage. Either everyone is having sex when the viral load is really high or there are a lot of other std's being spread around causing the elevated transmission risk. And why the racial division?
I have a question regarding the regional geography risks involved. You recommended another test at 3 months due to the persons geographical location, however was this also due to the activity performed? Lets say a person has protected vaginal sex or protected oral sex in Africa, would your testing recommendations differ if the person was say in North America?
Search the threads and archives. common in some parts of the world than others (i.e., in some populations than others), and the risks of vaginal intercourse higher, has been discussed. (Try searching old threads for "HIV transmission risk".) It's quite complex, but the expalanations include circumcision status of men, background STD rates, "dry sex" and other sex practices, average viral load, stage of the HIV epidemic (related to viral load), relative infrequency of antiretroviral therapy, and others.