Symptoms are never used to diagnose HIV as they can be confusing and not always specific. If you could tell us the kind of sexual encounter you had we could give you more accurate info, but if you really think you had a sexual risk, you should test using a duo/combo ag/ab test that will be accurate 28 days after the exposure.
What was your "medium low risk encounter?"
Also, symptoms would never show up after 3 days and would not be limited to a sore throat. Sensitive/red hands are not a symptom of HIV.