Thx for the links~

You're using pillow shading.  Basically, you're just following the outline with bands of color.  That's where most people start out, but all it really does is take a good design and make it look really flat.  I think your character here has potential, but she needs a serious reshading.  Think about the shapes you're working with, and consider how light would actually hit them.  If you have some trouble with that, break her down into shapes; her head seems to be basically round, so look at how light reflects from a sphere (this ref might help: http://www.wetcanvas.com/Articles2/6561/299/images/sphere-demo.jpg)  Her dress seems to (basically) be a cone, so again look for some reference.  Once you've practiced that a bit, you can move on to more complicated things; giving her dress (I assume that's a dress, perhaps a ruffled fringe under the mushroom cap? http://www.naturezadivina.com.br/loja/images/amanita_muscaria_2.jpg) folds and such.
I hope that was a bit helpful...

It's a nice design, but the shading on this makes it look flat.

Try to change the background color and you will see it more easily.

ek?! where is it? I can't spot it!!!@_@

There is a white pixel at the back of her head