Nude study and shading study

[chadrach]

I think the previous two posters gave you some excellent points to consider. I would like to add another one. Your subject is the most important part of your piece since she is the focus, but since you also decided to paint in the background, I think it is worth noting that the perspective is not quite right. In your painting, the angle of the bed is much steeper than the photo, and I think that is also contributing to the image feeling off.