Nice art-style and good concept! I liked the overall mood of the game but there are some ideas of improvments I wanted to share IMHO.
The menu part was difficult to aprehend with the inventory and so on. I thought the start of the game was about choosing a weapon for that specific run.
The main reason why is I didn't get the fact that when you don't move, the time is frozen. I thought it was a bug or a browser issue. So a quick intro on that mechanic would've been cool or something like a feedback with some UI element showing you that the time is frozen and it's normal, you have to move :)
For the controls: The aiming was confusing, I expected to use the mouse and click to fire. The movements are a bit slow paced for me. I could imagine something really more nervous.
By the way, I don't want to sound to negative because the game was cool and it must been have a challenge to do, so congrats ppl!