This was really good. Very nice animation and the joke wasn't predictable, it made me laugh.
You should probably consider working on the background elements in your work because I feel like you could push the depth quite a bit. By adding overlapping layers of objects (foreground, mid-ground and background being the main three) you could boost up the animation a lot. You might think that these things are such small things, that people wouldn't even notice them but they actually make more of a difference than expected.