It's good, but the problem is that the ambience is too high and the shadow is too uniform. The more you get beneath the hammer, the less light there is, and therefore there should be gradual darkening of shadow. The single light source and high ambience means that there's the same amount of light directly under the hammer as at the edge of the shadow, which isn't what happens. Here's a quick render to show what I mean (it took about 4 minutes). The shadow is not all one shade. The more "hidden" and area is the less light will get to it, hence the graduated tone from light to dark. I think that's why your hammer handle looks "weird". Having said that, I might be mistaken as I recently hit myself on the head with an axe.