Hair
Totally repixel and shade the hair, its way too messy and theres wrongly and randomly placed pixels you have too much dark shading of the hair which makes it look odd, also remember to shade it correctly on the RTP the light source should be coming from the top left of the sprite and on yours it looks like a mix of top right and top left.
Torso
The body has been shaded and pixelled weird, tidy up the pixel work on it and remember to make it slightly lighter on his right hand side... that being the left for you.
Legs
Same as the body, tidy it up and shade correctly.