wow... it was kinda strange reading this cos the OP was a good friend of mine but it reminded me of my last hardcore K experience... and unfortunately it left me troubled for weeks after (but equally respectful of the substance....)
All I managed to bring back from a similar dosage was "it felt like I was being repeatedly reborn through a shiny metal uterus. Every so often I would come around, experiencing a new baby's sense of confusion. Throughout the many cycles of rebirth, I was constantly tormented by malicious gnomes"
Funnily enough though, also, once it had worn off, all I wanted to do was go back and try it again.
The K experience can definitely be dark and scary, but it's like a great horror movie; it keeps you coming back for more in way that most unpleasant experiences generally don't.