Haha, fun concept. I got confused when it said I lost immediately and then I understood haha. Nice pixel art :)
I did come across what I think is a bug on the 3rd level where I couldn't jump up the wall, and then occasionally it would make me fly up to the ceiling. I also got a bug where when i got hit by a razor it would just keep saying 'Retry'/'Menu' and no matter how many times i clicked Retry it didn't seem to restart the level.
I think adding sound would be a great addition; some nice background music and a sound effect that happens every time you jump would make it even better :)
But otherwise, a nice idea! Well done!