You shot a hummingbird straight on and got sharpness on the head, I say, congratulations. The composition is what I am not liking much, maybe a more vertical crop. The dark area left above the bird left distracting and I only wish the wings were more outward. But hey, this is one hummingbird shot more than I've accomplished!
Nice image, John. I like the color and details you captured in the gorget. I think it would have been better to have direct lighting for a head on shot like this. That would have better illuminated the shadowed left side of the birds head. I am assuming you were set up on a spot were the HB was feeding and were not using flash. If you had moved a little to your left, you may have been able to get more direct lighting and eliminate the dark area in the bg.