I think you did a good job on the body and his tail. His paws could use a little more detail, but you've got the shape right. His face is a lopsided though, and one of his ears has an extra point to it. You did a really nice job overall, especially since this is your first foray with charcoal.
Generally I paint rather than draw, and use huge amounts of colour, so this is a big step away from my normal work. Thanks for the comments, I'll be extra aware of the symmetry in my next attempt.