I think you did very well in putting depth into this! I really love those lips and you did very good with the hair I can tell you spent a lot of time on it.
Critique wise I have to say there needs to be more color in the skin, don't be afraid of different shades and bolder shadows. I can see as well the nose is a bit long with how you have positioned the forehead needs to stick out more it's very flat. since the eye is covered up. Though i rather like the hair covering the eye there still would be a trace of an eye behind that hair on how you put it there it needs to be thicker right there, or have some kind of hint of an eye.
you did very well with the highlights in the skin, you got it to be very smooth. The lips are gorgeous like I said, but the upper lip may be a bit better if it dipped out a little bit!
over all it is very good! I hope my advice and opinion helped!