So first of all GG! I saw your new, and you said you where pretty young. So really good job, I also started with Unreal Engine with a 2D platformer. And yours was way better than mine.
The idea of the shop is good! There is only one problem, it the hitbox of the charater, but it's only a quick fixe.
The physic is okay, it can be improved!
Like I said, amazing job! Keep working, really!