I see you used lines, me gusta haha cropping around the thumb is a bit sketchy bit not bad overall brighten it up a little, unless you are going for a darkish mood for it : Blend the background in with the picture a little moarrr
Lol, I don't use lines much, not really my thing normally. I see that now that you mention it I was trying to keep it dark, but I think I'll add in a light source to make it a little more shadowed. Like a little fog?