Fun game!
The music is very interesting, but fits the style quite well.
I do say, I had some trouble trying to find the radio tower after running dry on ammo, and I also thought it odd that I can simply "cheat" by just standing on top of cars.
Maybe make the terrain easier for the zombies to navigate while still giving the player an advantage?
Overall you did a good job (I for one can't imagine choosing 3D for a one week game jam) so props to you! I just feel like it was a bit too easy.