the main thing im noticing is that your shadows are pretty grey-ish. maybe try saturating them a bit? since both the hair and the skin are warm-toned, a warm/reddish pink could work well perhaps.
also some of the shadows are a bit too soft, namely the ones on the top of the hair and the exposed shoulder. i see youve already used harsher shadows in other areas, so try using that same brush to make those shadows a little stronger and add clarity