Love the artwork. Very clean old-school style reminiscent of early 2000s Quake engine stuff. The rocket launcher and machine gun models were especially cool.
I kept running into the issue with enemies not taking damage, which is unfortunate, but hey, it's a game jam. Stuff like that happens. Still impressive for 48 hours!
I do think from a design perspective, having the guns keep spawning during the enemy wave or at least having ammo pickups spawn in would be a huge improvement. Even without the damage glitch it's possible to get softlocked by running out ammo.
Overall nice work, though! =)