You've made a lot of progress, but I think you need to stop refining it until you get the volumetrics right. The nose, left cheek and the area around her eyes look flat. I suggest looking into facial planes to get a better idea of how to shade the face as a collection of basic shapes.
This book might be useful.
I second the suggestion to look at references. Even if you can't find something that matches this piece, you can try combining photos from different angles (two images = 3D, right?
), and simply sketching random faces from photos might still give you a better idea of how to shade her.
Also, you could still benefit from moving closer to EvilEye's edit since she still doesn't have much of a chin.