Digital Illustration Critique

[weeazy]

Theres nothing that immediately jumps out at me as an error, but for some reason I don't like looking at it. I have a guess that the green is too bold and saturated, and the purple in the left hand corner was not the right call.

Would like to confirm these thoughts, but also looking for any additional critique overall

Sometimes, when something looks off and we can't pin-point why, it's usually the overall composition. To me, it is mainly a value issue. Your character is pretty washed out in all that light! Try turning this black and white, minimize it, and then squint at it. His overall silhouette blends into the lit-up part of the floor and wall. Since he's the main subject, depending on what you're going for, he deserves the according importance. I would either make the values on him slightly darker overall (if you want some really bright parts, stick to highlights -- where the light would realistically be lightest on the material, or a rim light) so that his silhouette is clearer in the picture by creating contrast between him and his environment. 
Here's an example value design. Notice how the subjects are made clear through value contrast. 
(Credit: Chaichan Artwichai)