Welcome to the forum!
I would not worry too much about the length of the petioles. They look like they are okay and will perk up more if cared for well enough. The plant can, however, do with some more sunlight.
You should probably change the soil. That looks like pure peat moss sludge (like half decomposed).
The watering looks off. It looks way
too waterlogged. Bring the water all the way down to half an inch - an inch of water in the tray if you can. The most ideal would be no water in the tray and keep the soil moist 24/7. Make sure you use distilled or reverse osmosis water. (Most) regular tap water will burn the plant.
As for pot size, it should be okay for now. It is a bit difficult to tell the dimensions of the pot, but it isn't unreasonably small. It just wouldn't hurt to plant it into a larger pot.
If you have any more questions, ask away!
"Complaining about a problem without posing a solution is called whining." - Theodore Roosevelt