The game was quite nice. Not really original but that doesn't really matter if game is done well as in this case. I liked the concept. While I know you did this in a week, here is few suggestions to improve the game:
* Music loop could be longer, it gets really repetitive after a while.
* Screaming sound's quality is a bit bad. Might be just my opinion though.
* Menus could use some small animations. For example when I complete the level, I see the skull falling. It would have been nice touch if it had fallen to the neck of the skeleton in the score screen :)
* Like already mentioned, speeding things up might be a good idea.
* Gameplay wise I would have liked to see the whole level before hand to plan things out.
Hope this review doesn't feel too negative! I think you did a decent job especially considering the time and prototypes are not meant to be perfect anyway :)