I have no influence over those who downvoted you. You will just have to work on recovering your reputation and get rewards on new posts. Look into the art communities and contests to get seen and build connections. Have fun with it.
I saw you added a link to the artist who inspired you, but given that this was a close copy I think it might be better to start the post saying that they inspired your drawing. I am not one who attacks artists, but some people may think otherwise.