The concept speaks to me, as a person who can't sleep with even a drop of liquid still in my bladder, but I think it needs a few more tweaks.
The fisheye effect makes navigating through doors more difficult throughout the game.
The initial toilet does not always recede if you approach it at an angle, so I was able to climb on and around it. It took a while to figure out that I needed the toilet to recede a certain number of times.
The room with many stalls has hitboxes for the doors that are too big, maybe? It's very easy to be trying to close one of the doors you have opened (otherwise you can't get past it) and accidentally click on a "bad" door beyond it by mistake, setting you back to zero. I did appreciate that you added hints in there, as well as the hints in the maze.
Despite the hints, in the maze I still got completely lost. Tried following the light hints, but couldn't always pass through a door/wall near one of the key lights. Tried following the directional hints, but was not able to go left the second time; no door/wall passage in that direction. Spent more than 20 mintues going in circles, and that's too many minutes for a game about toilets.
It's an interesting and fun concept, so if you ever decided to come back to it to make any adjustments or additions, I'd be willing to give it another go.