The sharpener in this context is about sh

The whole song has a generally pretty clear meaning but some lyrics i wanna go into detail about (as a person who has gone through similar).

"Sometimes seems like Im still young, looking at the boy across the sink. Thinking "What the hell have you just done?" " - Speaking from experience, after sh I sorta feel like 'why am i insane' 'why do i do this' 'why am i doing this' and i have never heard a song that really displayed these feelings.

That was just what i wanted to express with this