Freakin' sweet. :3
Very nice. You've got great animation skills and storytelling ability. The choice of music worked really well.
My only critique is some of your pacing.... There are parts in the animation that last a little longer than they need to, like the amount of time spent on the gun in the locker. It's honestly just small, and I do mean small, amounts of time that need to be cut in order for the urgency of the situation to take effect in the subconscious mind of the viewer. Since the music tempo is rather fast paced, the bits of extra time are accentuated as well.
But seriously, great job - 10/10 5/5 I'll look forward to seeing more of your work in the future! :D