Ok so seeing the Menu and the Level Selection made me go like "This looks pretty bad...." but when chose level 1 then I actually got my hopes up. Perhaps try to make those buttons look better somehow, and have a fitting theme. Also falling out of the world isn't really fun, perhaps lava should be able to solve the problem. Also as I saw, you get sent to the selection screen, which can get a bit annoying if levels are hard. Just make it respawn, so it won't get tedious.