Since you had Unprotected Anal sex HIV testing is needed at 3 Months. Unprotected Anal, Unprotected Vaginal and Injection Drug use are the main ways you can get HIV. Symptoms are never a clear indicator because the symptoms you could be having could be something totally different from HIV. Plus ARS Symptoms happen usually between 2 to 4 weeks and resemble the worst flu you can imagine. If you want more information go to www.AIDS.Gov or www.Avert.com.
to begin with you , you had a risk and you need to test for it and also hiv virus is not very easy to transfer its hard virus to transfer , all i say be patient and test at 4 week with 4 generation , and just
do the 12 week , that test is more your peace of mind as some guide line still say 12 weeks
Hiv duo combo test which detects the p24 or the hiv antibodies 1/2 at 4 weeks should be nearly conclusive .rest official guidelines are 12 weeks post exposure
Your fever started at a time not common to ARS symptoms that starts around 2-4 wks.
Much needs assumed to say you'll be positive.
You did have a high risk. 28 Days post this event take a 4th generation duo test.