Hi, I think it might be worth pointing out why people are complaining.
First off all the colours are very bright and saturated, much more than they need to be, especially for a dark and moody scene.
The models are very basic, that blue thing in the corner, what is it? It might be worth looking into modeling techniques and reference to add the details you need. The toilet looks like it’s made of primitives. The seat shouldn’t be a simple torus, for instance. Look into poly modeling tutorials to see how you can model it properly.
Look into using Mental Ray for your shading and rendering. Everything looks like it’s made of a Lambert material. Most surfaces in real life have at least a little reflection (even if very soft and blurred).
Hopefully these tips will help you make a technically improved image, good luck.