Had a hard time playing it. Really neat idea. I love gravity game. A few thoughts:

1. Music on the main menu would pop it up a notch.
2. Unplayable with a gamepad. The right stick look was so slow, I had to go to keyboard/mouse.
3. You can get stuck in the first room if you shoot your gun too much and run out of ammo before realizing you need to shoot the pulley.
4. Grandma walks way too slow. Sure, she's a grandma, but she has a tracksuit on. I expect her to be a powerwalker. I saw you could run with shift, but I had to hold it down and that was annoying.
5. The gravity switch is WAY too slow for an FPS. I was just standing there waiting for it to engage. Not fun.
6. The gravity grenade is hard to throw. When I finally did, I don't know what I actually pressed to get it to go. I also think I threw it in the wrong direction.
7. When I went through the hole in the wall in the second bedroom, I got stuck on the entrance wall, couldn't move and got ganked. I then quit.
8. I had to task-slam the game to get out of it.

I think you made a really ambitious game in 10 days. Props. I ran into a lot of issues myself and ended up with something without game mechanics. You had a ton of cool mechanics, but the levels weren't playable enough to be any fun.

Good job submitting a game for the game jam! I ran into a lot of bugs that soft locked me into not being able to complete it. Here are some things to note:

1) The UI indicators for where to go and what to shoot moved all over the screen, even with me just standing there, so I was not sure what I could shoot. I ended up using most my ammo trying to shoot at different things until I shot what I guess was supposed to an elevator.

2) I could only look over my right shoulder, so the first few enemies were able to see and shoot me when I could not see or shoot back, making it a little frustrating.

3) I tried interacting with the gravity flip mechanic and it would not work for me in the tunnel, no matter how long or short I held down the 'e' key for.

4) I was unsure if those enemies I pulled in with my gravity grenade were dead since I could not shoot them (or at least, they did not make any sound effects) So they all got up and shot me unexpectedly. (Maybe some indicators of what the grenade is doing and more sfx to let the player know they are not dead- it sounded like they could be since they were silent)

5) When I ran out of health, I did not die / restart, but continued to get hit

6) Once I ran out of bullets, there was not way for me to fight back so I ran around with no health trying to figure out what to do next

7) the gravity shift did not work in the narrow wall after the second room, so I got stuck

8) Sometimes I would be able to see through the ground / floor / ceiling

I am only listing these to help so you get an idea of player experience, so I am saying these in the nicest way possible, hoping to help you! It seems to me that there are a TON of mechanics in this game which is awesome! It just might have been so much in scope that a few things fell off such as playtesting. I love all these ideas together and I am sure with some polish, this will turn out to be a great game! Good job!

It's fun! 

Nice gravity mechanic and overall idea. Looks promising.