Nicely done. Congrats on finishing this in 48 hours!
For the most part, your different guns felt pretty good, but there lacked some variety. A lot of the just felt like "shoot with a different cooldown and damage", but the weapons with unique properties that I saw like the shotgun (and especially the chainsaw!) were the most fun.
A really tough design problem I've seen a lot of folks encounter this jam is coming up for 6 fun and meaningfully different abilities when doing "get a random ability" designs. It's hard! And with the absolutely huge amount of guns in here, I'm guessing a lot of them are just variations of each other. That's the sort of nuance you can get into in a full release, but for a short & sweet jam game, less is usually more. I had the most fun with your game when I was getting a completely new gun to try out. But when I rerolled and got something that fired slightly faster but did slightly less damage, it just wasn't exciting. Get playtesting in and find stuff like this to help find the most fun parts of your design!
As for the movement speed - at first I thought it was way too slow. But I actually came to enjoy it. The bullets are slow, the enemies are slow, and the reload is slow. It gives it all a kind of lightly tactical feel. You need to be thoughtful about your movement and the game gives you the time to do that. The low ammo count on some guns makes this okay because you're constantly trying to adapt to a new playstyle. I think that worked pretty well.
Wew, wall of text. Woops! Hope you enjoyed your jam and learned something new. Keep making games!