Blood "Complete Picture" (CP) does not tell you about your infection conclusively. You need to go for the specific HIV screening test after a recommended window period.
Symptoms too, do not indicate your HIV status accurately, in fact, they are confusing and misleading most of the time.
As you were exposed to the risk, through unprotected sex with someone of unknown health status, you should get yourself tested HIV where 4th generation Duo (Antibody + Antigen) test is conclusive after 4 weeks of exposure. Get the test done, collect your conclusive report and move on with your life
ARS symptoms don't start this early, they show up after 2 weeks. The fever you are having could be because of some bacterial infection.
Since you had unprotected sex, so get tested by a 4th generation duo test anytime after 28 days of exposure. The results will be conclusive