I agree that you shouldn't feel bad about the changes. This is your first project and learning as you go is the norm. I'm sure there'll be other changes later, as well.
Oh, and as another example for you, Cosy Creator did something similar with Cosy Cafe. Originally that was going to be a sandbox management sim, but Cosy figured out after his first release that it was just going to be too much trouble to make sure the story he wanted to tell worked within the sandbox mechanic. Since he'd only put out the initial release, he just stripped the entire sandbox system out and converted the whole game into a fully kinetic version instead.