Interesting concept. I liked how the level builds on itself as you progress but I also felt when it started to get near the end redoing the buttons every time was getting a bit tedious. I also like the effects added. A little advice on screen shake is that if you add a little bit of rotational (as in rotating the camera2D) shake to your translational (as in up and down and side to side shake) shake it looks even better. Here's a good talk about implementing very nice feeling screen shake.