I think the piece is perfectly fine as it is, I didn't mean to imply you needed to change anything. I was just curious on your thought process, which appears to be through-composed, which is perfectly legitimate.
While I think it is important to have an organized structure, at the same time you don't want to be too organized. I think it's important to find a happy medium between planned structure and letting the music flow naturally, which I think you did. It kind of sounds like you started out loosely with the idea of a sonata form, then improvised within that mold. As long as you keep practicing like this you will only get better over time. The thing to ask yourself is "Was it too through-composed, or was it too organized?", make an adjustment, and implement on your next piece.
PS, didn't mean for this to turn into a review of your concerto, but good work! 😆