ok. for a attempt Id say you are in my top 5 =P.
Some things you need to work on...
1) You need more contrast!
2) Shading isn't pillow shaded (that'' a good thing) it's just messy, you need to clean up you shading.
3) The mask, the light source is on the wrong side (usually comes from top-left) and it is too noticeable compared to rest of the sprite.
4) The bracelets look like they are cutting circulation of the wrists, where the arms connect to wrist. It looks like the arms are balloons tied off at the ends.
That's it so far. Try to remember the contrast, messy shading, and light source issues for your later sprites. And remember to keep an eye out for the HKCP, the Christmas contest will be up and running soon. I hope to see you compete.