The guy below :S
I can understand all the people below saying that this was absolutely amazing because it was pretty intense but there are a few things that the guy below me was a bit too harsh to mark so quickly.
The whole "Shivering" concept was rather good, i enjoyed the way you've taken a lot of other animators style, that being the well drawn and dramatized animations, and made it your own. At the same time though i did feel as if i was playing a game so that's a huge plus on your part.
The ripping off the arm part was really good but i did worry about why it fell off, I then see two seconds later a guy with cables on him and a chainsaw... Problem solved, some form of Science fiction.
The voice-overs were a little off at the start but it worked.
As the others said, make some more and you will get far on NG.