The speaker is telling a small, painful story about timing. They got so wrapped up in the dance that they almost missed their chance, and the language suggests they were trying to keep up or compete with someone else, nearly losing their rhythm along the way. The dance seems to work two ways: it could be a literal dance, or a stand-in for the push and pull of romantic attention.
The last two lines are where the real feeling comes out. The speaker admits that "she is the one for you," so they accept that the person they care about belongs with someone else, or at least seems to. Yet the heart won't go along with what the mind knows. That gap between knowing and believing is what the poem is really about.
The mood is wistful and quietly bittersweet. The short, bouncy rhymes sound almost light, but they sit against a sadness the speaker can't quite shake, which makes the ending feel honest rather than dramatic.