Reverie

I would keep a sketchbook with you with good quality paper (50 or 60 lb). So if the mood strikes you you will be ready to go. Your sketch is just fine. Let's have some more.

I think this is very lovely! It might just be me, but I think the back of the skull needs to come out a little more to give it more volume but it might just be her head shape.

There seems to be some issues with proportion in this image. I would say, even though shading can look great, take the time that you are using for shading and instead use it on a second pass to measure the parts of the face against each other. :) For example - how big is the eye in relation to the nose in actuality? How big is it in your image? How many eyes could you stack between the lips and the actual eye?

Great work, keep going! :)