"Occupided"? Lol aside from that, yeah, that really sucks. FYL.

Can you deal with people crawling under the stall to check?

Carry a squirt gun.

They want to see if you're close to finishing. Are you wiping your ass or posting hilarious comments on FML?

Couldn't be bothered to say "Someone's in here" after they jiggled the door?

I think OP means that they still peek after doing that. Or they just straight up peek which is creepy.

How dumb can people be?

Now if they were quite young I could understand as people sometimes lock the doors then squeeze underneath as a prank but in a workplace that's weird