Well done for a beginner! Done some nice things that I think some people would forget to do!!! Remember not to use black/brown for shadow on skin - will make look muddy. Instead pick a light source and choose the colour that light source would cast !
The gentle brush strokes used on the woman's hair does a great job simulating its silken texture and jet black shine. Her glowing green eyes are an amazing focal point for the subject's face and immediately draw my attention toward it. The subtle shadows in the pits of her eye sockets have a rather realistic look toward it and really stand out well. For a beginner, you have already shown a great deal of potential in this style and I can really see you getting better and better. Good job!