Game is fun and audio is really great, but in my opinion jumps are too high and gravity is too low.
I also found one annoying bug. I had to release my E button really fast, otherwise I enter to next room and then go back to previous room.
I also suggest to look at graphics. Some pixel-based sprites are bigger and other ones are smaller. Try to use the same "Pixels per unit" value for all sprites and set sprite size directly in your painting software.
The rest of the game looks very nice. Good job!