This song is definitely about drugs, in all honesty. Billie was singing about how it was to be high when he was younger in his room, it's pretty obvious. "My mouth is dry, my face is numb, f*cked up and spun out in my room," is just one of the many clues that shows what the meaning is behind it. And not being able to sleep is one of the many side affects to certain drugs. And also "My sense's dulled, passed the point of delirium," are some other context clues that prove this song is just about drugs.