Wow, welcome to DPC. From your comments, you've probably realized that DPCers can be pretty cruel.
The lighting for this is a bit harsh, and I think makes the photo look a little grainy. You might want to check out the nude gallery for ideas about how to be more flattering for the nude body. Because skin tone can be so finicky (I'm a redhead so I have to deal with my pink skin tone and freckles), I think it's particulary difficult to photograph. Softer lighting is probably better. Also, how you pose the model can make a big difference. For instance, even skinny models can look chubby when hunched over so that their stomachs bunch up. I like the pose in your profile picture better (I probably would have fallen over).
Better luck next time. Don't let the DPCers get you down.