Mine is when i was in band class (I play mallets and most definitely in treble clef) when i randomly started reading in bass clef and couldn't snap out of it so i started playing weirdly
When I realized that in the song ‘Poker Face’ by Lady Gaga, she doesn’t say “P-p-p-poker face p-p-p-poker face” in the second chorus line of saying “Poker Face” she says ‘p-p-p-poker face f-f-f-f*^k her face’
(if this is too inappropriate ill change it just let me know!)