Death

This picture in general is mysterious, enigmatic, and the calmness of its tones make it almost alive, as if death were still lurking behind us. The technique is still unachieved, although it's remarkable that your sketches range from softness to sharpness, that shows that you're experienced with pencils. But with so much pencils (2B to 7B), I think you could have avoided to do those crosslines. I mean, you could have tried to make softer gradients instead.
I like the hand, I think human hands are the most difficult thing to draw, and this one respects the proportions and shapes of a real hand. The shading is clean, the position is perfect. The only thing I don't like about this hand is the shadow. In fact, shadows in this picture are very confusing. In the hand, the shadow is very well defined, but it doesn't seem to match the hand. In the table's shadow, it seemed like you tried to make a specific area darker to make the paper contrast with this shadow. And the pencil, it looks good as a symbolic element, but it is so dark and sharpen that it distracts from the hand.
The composition is very well done. As I said before, the hand, even though it is in the right side and not in the center, catches easily the viewer's attention. The straight thing on the other side... I don't guess what it can be, but that's part of the mistery in this piece. It could be a halogen lamp, a tripod to hold photo reflectors, etc.
Just work on the shadows. Think in 3D, see how shadows work, imagine the light coming from a point in the space, hitting an object and leaving dark behind it. Follows the light rays from the edges of the object to the floor, that way you'll get an idea of what should the shadow look like.
(BTW: I know my english sucks, but I try to make my best.)