Good job on capturing the main features and making the character easily recognizable :)
Some tips: you can adjust a drawing to fit the story, so adding the lightning bolt would definitely strengthen the image .
Next is the wand, little details matter for big fans. (The shape is very different)
I also recommend to use a paper over the drawing where you hand is resting, to avoid smudging the pencils.
And lastly- as this is based on Radcliffe, his face is a little longer, you can see it most noticeably with the nose :)
Good luck and keep it up! Upvoted ^ ^