"
So sick... There is a snatch of an old song
Blaring inside my head but I know I ain't dead, no.
This can't be hell: I'm way too cold, I'm shivering.
The cold sweat is like broken glass;
Isn't this a gas? Come and join the party
Now he's describing heroin withdrawal, which is characterized by hot and cold sweats, flu-like symptoms, significant pain, and an overarching sense of ennui.