"Head over heels" is actually a corruption of "heels over head".
It's one of those corruptions which flips the meaning (ironically, in this case!) on its head, or just becomes meaningless over time as it's reinterpreted (like "the exception that proves the rule" or "begs the question").
It isn't even true.
https://xkcd.com/357/
"Head over heels" is another weird idiom. I'm so in love, I'm standing in a normal orientation.
"Head over heels" is actually a corruption of "heels over head".
It's one of those corruptions which flips the meaning (ironically, in this case!) on its head, or just becomes meaningless over time as it's reinterpreted (like "the exception that proves the rule" or "begs the question").