The camera was too slow, most of the time the player is out of the screen. In my game, I've made that the camera moves every frame one-fifth of the distance between it and the player so its velocity changes depending on the distance to the player.

I think that the hitboxes are too big. I've died when the sprite of the cat had not touched me yet. You should make them the same size as the sprite or a bit smaller.
You could add more feedback. For example, you could add a wait time after you die so you can see why you died.
I liked the graphic style and the sprites.
It was pretty fun although the camera made it a bit frustrating.