I have included this wonderful tutorial artwork in the new feature for July 2014 on the front of the journal. Please the journal so that more members will see your art, and thank you for being a member
There is a general feeling of "grey" in the skintone and since it doesn't appear on the hair, it can't be felt as coming from the (relatively) light background. You may try to allow more saturation in the shading of your skin palette ? Playing with levels on the file of your tutorial worked pretty nicely for me, proof enough it's a question of "feeling the color" and that the technique of shading is excellent !