Good use of soft brush here, but there are some fault like on the nose, don't you think the nose is too round and big? And on the hair, I think the center of the hair on the forehead, it's too backward.
I really like the dark contrast in this piece. It's powerful and really sucks the viewer in. Especially with the hair acting as a sort of veil. As you continue you render this, don't lose that veil feeling.