I really love the colour pallet you chose for this! It's so whimsically awesome! Using purples for darker tones... Me Gusta!
My only suggestions at this time is the eyes and nose.
One of the eyes is alil off kilter but then again, some people have eyes like that, it's rather normal!
Well I can't really offer too many tips on the anatomy as anatomy varies from person to person and since I have not a clue of what you look like.
However... What program did you use?
If it was photoshop and you're into portraiture... Try out this
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