The artstyle is nice, it makes me think of Mirror's Edge with a twist!
I think it has a lot of potential as a fast-FPS, but the lack of feedback (sound, animations, readable shots, displayed player health, etc...) makes it really frustrating to play, If I understood correctly, I can only have 3 powerups ? I'm not really sure of what they do either :/
But it's still a nice entry, there is only so much you can do in 48h ^^ and without a doubt, if you had just a little bit more time you could have solved all of these problems :D
Good work!