Very impressive for a first submission! The art is very cute, and I really liked the sprite animation for sliding under! very creative!
The debug speed didn’t bother me, I actually liked being able to see it :D
Some possible improvements: the final jump in level 2 is quite difficult (luckily the save point is right there). In level 3, I couldn’t get past the first door.
To bring it to the next level, you could add music and SFX.