Figure with Black Hair

This is an oil sketch on MDF. Its a young woman with black hair, from a drawing session at Fall City art studio last Spring.

I'd like to paint this all over, now seeing how sort of skewed it is. But it represents a direction I'd like to pursue, to get good at. If it were dead on accurate- and I don't really mean as a likeness- I'd be happier. And I haven't really figured out the green thing- the shadows on white bodies that look greenish, but aren't really.