Great game overall! I had to stop playing at the 12th level because I changed window focus and the game ceased to accept any input (I was playing through Wine so I can’t complain). 20 levels is pretty impressive though, good job!
The shaking gets annoying pretty fast, it would be nice to have an option to disable it.
The first level was the hardest for me, because it’s very difficult make the final jump simultaneously. You could make it so all the levels are unlocked, because it can be a significant barrier for other players.