Very nice post processing, and even though I'm not a fan of selective coloring, I like your use of it here.
I would give you +1 for story-telling and technique. Excellent choice to have the blurred hand . . . but it may be a little "too blurred" . . . would have been nice to have been able to see the image of the hammer.
This is one of those photos that leaves me "wanting" . . . I can't decide if there needs to be more in the composition or less. Also, the angle of view is pretty ordinary. I realize that at a fair, it might be awkward (and dangerous) to lie down on the ground with a wide angle lens and get the hammer coming down on the shoe in the foreground and the rest of the farrier, slightly out of DOF.
So I would give you a 10 out of 12 (-1 for impact and -1 for creativity) That's just my opinion. Nice work . . . keep it up!