One thing I learned (and I am new here too) is to not let the eye farthest away not have the smallest amount of skin show around it. The model, if turned just a tiny bit more to the camera would have prevented the eyeball from floating in mid air on the edge of the background and the the tip of her nose would have been inside her skin rather than peeking out into the background. Do you see what I mean?
Good Luck with your efforts, I like the black and white, I don't shoot in black and white and I really enjoy seeing others do it.