The major problem I see is that the tilt of the eye line is wrong. If you draw a line across the eyes in the ref pic you get about a 4:1 slope. In the pixel version it's 8:1. This would be ok if the whole head was tilted, but the nose and mouth match the angle of the ref photo, and the result distorts the whole shape of the face.
I suggest you pull the eye on the left down quite a few pixels and then rework the cheek and jaw lines like Mathias pointed out.
Tourist