This is an unstable game.
You get half the points available becaues you didn't really polish this game.
At all, it feels like.
First of if you got enough speed (which isn't that much) you can zip through the walls, and you can also go through most objects without much speed.
Another thing, the whole bouncing physics are annoying, it is unstable and tried to be realistic, but that is just bounding to problems.
You get a 5 for the good stuff tho, good idea, next time work a little harder tho!