First lots of thanks for such very true interpretation, like the article for its lucid continuity👌👏

EXCUSE ME PLEASE for my intervention 😊😌☺
There can be butterflies in the heart 💛, but how can be in stomach (sometimes English Proverbs have irony both in verbal and situational sense);
because love focuses on its own target as it is an abstract concept - it pains heart, it relieves heart, it arises in heart, lives in heart, curbs or congeals heart - when love goes through abstractions, the extraction of the same manifests itself in concrete factors by the agency - man/woman in action and through the body - then ❤ has its own expected outcome (Love's own targets to attain desired subject or as an object) and unexpected outcome ( Love as disruptor of focus, which is beyond the understanding of Love's target).
So butterflies in the heart fight to locate their flight so not to be a part of Love's labour lost. When it happens so, subsequent parallel pattern is then "the butterflies in the stomach"😏🤔