What does 'you have broken a feather' mean in the ABBA song Chiquitita?

The Spanish version makes this idiom a bit more clear, "You were so self-assured when I met you; but now you've broken a wing" - the whole song has a bit of Word play: a chick being a little bird; and chiquitita being Spanish for a young girl. So the broken wing, broken feather analogy is basically saying, "You used to be able to soar/fly because you were sure of yourself; but now you are wounded, unsure - you have a broken wing/feather and can't fly/soar like you used to".