The only risks for HIV in adults are:
1) Having unprotected anal or vaginal sex, or
2) sharing intravenous needles with IV drug users.
You were never at risk for HIV. In any case, you wouldn't get a sore throat from HIV 2 days later, and that's indicative of a bacterial or viral infection. Analingus could have resulted in the throat infection, so you should get your throat checked out by a doctor. It's not HIV, and any test you take will be negative.