Ooooj, when i played i found it really clean !!
The thing i think you can improve : Have a mouse when we are in the main menu !
Maybe have a little indicator for see how many jump you still have
When you fall, it happens so fast—it would help to have a little air time.
Maybe let the player be able to jump when we are on a wall, i feel frustrated when i'm in because i'm not in the ground and the mushroom say we cannot jump in the ground but i'm not :ccccc
Hope it help you !!