This game is actually really good, but i had some problems with lag while playing it. You did a nice job with the physics and all that stuff. I just reccomend you to add a background and improve Chicky.
The game is pretty good and challenging. However, it would be better if there are some musics and sound effects. The graphics are simple and nice. Where is the menu button, though? You know, so that we can have the option to restart, quit, etc?
I found a bug within the game. When I was trying to avoid the green potions, I went far to the left and disappeared completely from the screen. I first thought that it connects to the other side of the screen, but it didn't. I tried pressing the left and right arrows, but the character wouldn't show up, and thus, resulting in hamburgers filling the screen.
Aside of that, great job and keep it up!