I thought in the song Two More Years by Bloc Party They were singing Doom on You. Which is a friend of mine's favourite expression.
I felt a bit silly when I realised.
A childhood belief about misheard lyrics

others believed things like this
- My friend told me she had invented the expression 'Gordon Bennett' and I believed her!— SueE
- My friend's sister believed the lyrics to Gazza's "Fog on the Tyne" were "Fog on the dinasaurs mine all mine"— Suzanne
- I thought the song "Party Time" by Moby was actually saying "heart attack" (this was before I knew the title)— Elviessa
- That song that goes:
I'll never let you go...
I thought he was singing:
Another machine gun...
Haha.— Kelle - I thought that the song "Hands off she's mine" by The English Beat was actually saying "Anton, she's my aunt"— Nate
- The buckinghams song "kind of a drag", i always thought they were singing, "Canada Dry"— bobbybobby