A nice challenge! Especially good for a first jam! Great art and a cool concept
I was only able to beat the first level, for some reason (probably because my computer isn't very strong), It started laggin quite a lot after that, but the parts I did play were fun! I liked being able to go mach 5 as a dashing rat. My one little critique would be, in the tutorial area I dont think you needed to add the text saying the goop on the floor slows you down. The game already does a good job explaining that to the player without text, so let your game do the talking!
Good stuff!