I like it. I'm not usually a fan of this type of artwork, but it caught my eye...you did well to capture the emotion.
I kind of like the brown lips because I think that anything redder/pinker would stand out too much. The brown just lends more unity to the face. Either way, I think you did a great job with this! The use of light and dark values is perfect, and I love the shading as well. I'm actually very surprised that more people haven't commented on this, especially with all the excitement over 300.