As far as likeness goes....I'd say that you could really benefit from higher contrast between shades, as you've got a good start in on the right picture.
I think if you make the canvas a bit bigger you might be able to make it look a bit less pixellated

....also, I think if you didn't save it as .jpg it might help a little bit...try something like .png or .gif

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edit:
don't save it as .jpg then .png?
