It's hard to tell what things are. Generally it's a bad sign if you need any words to get the viewer to understand what's in the picture. Try blocking in colors and shading from there while trying not to obscure the form of things. WIth that technique, those hills in the background could be mighty mountains instead of nondescript collections of 1-2 touching pixels and the thing in the top-rightish bit of the sky (a cloud?) could be an eerie mist (might be a bit hard to pull off in 2 colors though. Scratch that could bit then). Composition-wise, there could use to be some more space around the moon so it's not in the very corner.
