I had fun playing this game! Really nice job with the theme. I'm a fan of the MS Paint styled graphics - feels playful and whimsical. The music didn't feel totally connected to the game, but it was also fun and didn't sound bad.
I'm not a huge fan of games that need a tutorial. I prefer games to teach me the mechanics by playing the game. For instance - you could have taken the tutorial levels and built those as the first levels of the game, and it would have been just as fun.
Nice work!