faces are not symetrical, and drawing rules cannot always be transfered. with some portraits it`s better to not put them in the portfolio ( because the person itself is not so pretty). this is one of those portraits. from a technical view, it is ok, except one thing. i see lines ! you did line the hairs. better don`t do that. only do shadows and shapes, no single hairs. also the eyelashes are just a few lines. try a 7 flat shader and give them more volume. no critique just some tips.