Good game, especially since it looks like this is your first one!
A couple of easy tweaks to make the game feel and play better:
- The character feels slippery! There were times that I tried to turn and the character kept going in the same direction, like he was on ice. For a game like this, I think making the character start/stop instantly would make more sense. Or at least turn the sliding down a lot.
- Try not to hide books behind the counter in the bottom! It was hard to figure out where the last red book on the first level was hiding.
- The last level was very challenging. Just an extra second or two would make a big difference.
- Your counter seems to break after the first level. It still counts correctly, but the color and the words are incorrect (picture below).
Really great job! I played it to the end, and I think your art looks much better than mine! 😄