Great work for being 3D! The guns felt alright, However i wish i could use them for longer. It felt like each room was very big, but extremely empty. When it wasnt empty, the enemies were much to powerful for what you could do.
I love the audio, it sounds great. Maybe giving some interaction buttons would be great for picking up weapons/ammo, i had a hard time getting them from the shelves sometimes.
Overall a solid idea, fits the theme! Great work.
edit: I loved the menus too, great job with those