Your signature looks like it's a scraggly beard. Couldn't even tell that that he has kangaroo pocket, it looked like his hand just disappeared into a bag. The bottom half of his face looks too big, like it expanded. The face shadows look splotchy. The tips of the fingers are too long and the finger holding the cigarette looks weird, I can't explain how, but it's off somehow and the creases look weird, maybe too long or going in the wrong direction, hard to tell. The angle of the pocket doesn't match the angle of his body and neither does his lower half. The front deltoid looks too short and the crease where his arm meets his body is not at all what that looks like, ref would be of use here.
I'd say so some studies of shading. You got the right idea, but it looks like you need to both tighten it and practice more.