The speaker admits right away that letting go is hard for them, and that their mind won't stop circling. "Overthinking" is the thing they're best at, and they say so with a kind of weary honesty. What follows is a push and pull. They insist they're independent, then immediately say they want the other person close. The words "Not that I'm not" feel like a small defense, as if the speaker expects to be doubted.
The tone shifts toward control in the last lines. "I'm the one in charge here" sounds confident, but it reads more like a way of covering up worry. Someone who feels secure doesn't usually need to announce who's in charge. The final line, "You just gotta wait and see," leaves the other person, and the reader, hanging.
The mood is restless and a little guarded. The short, casual lines sound like thoughts spoken half aloud, and the speaker seems to be trying to sound sure while feeling anything but.