You wouldn't happen to have the reference's url, would you?
Now things:
First off, you shouldn't work on a pure white background because it will affect how the non-background colors look to people.
You're pillowshading a lot of it, meaning you're using a lightsource directly between the viewer and the subject. This is bad and confuses the forms a lot. You should pick a different lightsource and stick to it.
Also, you have a lot more colors then you need on the skin and pajamas (or whatever they are).
