Fixing stuff in order to get it out of the uncanny valley:
-removed "dead body" skincolor
-removed amphibic feeling slimey texture
-fixed the proportions of every feature of the face, all of them were too big
-fixed the positioning of the eyes
-exchanged the male eyebrows with female ones
-edited the right cheekline
-fixed the shape of the lips
-fixed overall values
-fixed the crown of the head / origin of the hair that it doesn't look bald up there
-fixed some things regarding lighting
uncanny valley problems:
all of your parts are too big and too round.
You emphasize texture over light, where no texture should be visible.
Your colors don't model a believable living human face, your colors remind me of the makeup of monsers or "dead skin" gradients, not helpful to portray a beautiful female.
You get bogged down in working on details, while your basics aren't strong enough fleshed out in the sketch to actually paint it in a realistic style.
Focus on proportions and structure, it is definitely missing in this basic sketch you posted. You currentlycarry all those issues throughout the whole piece and even my edit is twisted in spots, just because i fixed thing by thing,instead of starting from scratch, whcih might have been the better idea.
Ok - one of firsts backups - to show where I started 
