Nirvana - Blew Lyrics Meaning

A blow job? I went to nirvanalyrics.net, which interpreted it as themes of constriction and entrapment. What Wikipedia said was pretty similar, as well. And if you think aboot it,
"If you wouldn't care I would like to leave/
If you wouldn't mind I would like to breathe/
Is there another reason for your stain...
Here is another word that rhymes with shame....."

I would like to breath, sounds like he felt constricted, and couldn't metaphorically breathe. And stain, word that rhymes with shame, sounds like he's talking aboot how that person/those people were holding him back and shamed him. Besides, Kurt Cobain felt pretty held back in his life. The ex he wrote aboot in "About A Girl", the people who didn't believe in him in "Scoff", being under a bridge in a muddy swamp-like area in "Something in the Way", it's aboot entrapment, not blow jobs....