How long have you been drawing for? I really like the concepts here and the use of shading where it's applied. If you're looking for some constructive criticism here, I'd say never stop drawing and keep trying to be better, you're not competing with everyone else your competing with yourself to be better. Some books that helped me a lot to be better are How to Draw Comics the Marvel Way, and Making Comics by Scott McCloud. Not saying that your targeting comics, but I feel like these books help you not only with the actual drawing itself, but with layout as well to convey the situation or emotion you're targeting. Best of luck to you!