Since you are unsure if any sex happened or not, and if sex did happen it could have been without condoms; you might have been exposed and at risk. Get tested at the 8 weeks mark for conclusive results. Good luck and I am certain your results will be negative.
The chance of HIV in this situation is very low, but not zero. Your sore throat doesn't mean anything. By itself, that's not a symptom of HIV -- there would be several other symptoms as well. But you need to be tested, both for HIV and other common STDs (gonorrhea, chlamydia, syphilis). Probably the tests will be negative, but better safe than sorry.
But the main health issue here is alcohol. You clearly have a major drinking problem: getting so drunk you pass out or black out, even once, is one definition of alcohol addiction. Deal with it.