Thanks! Thinking about it, the game over screens were somewhat of a last minute addition so they may actually be bugged.
And yeah, if I decide to polish this up I'd add some icons to the screen to indicate when an ability is ready, how much it costs, and whether it's available as well. There's a cooldown for each one.
You can actually knock things down! For instance, the objects on the tables in the piano room are all interactable. They don't really do much except pick a random direction and move slightly(also all of them move at once for some reason?) but they are interactable.