I assume you mean isn't, instead of it's, Jon?
Your stars are a bit wonky. And your sky is bright.
Here's my approach to the sky (Note that this is part of a collaboration with Xion):
Note how they're small, and there's a lot of them, a lot of which are hard to notice at 1x zoom. Your's are all the same size and brightness, which is huge and freakin' bright.
The moon, also, wouldn't be quite so... crescent. You gotta think, the shadows on the moon are from where the Earth blocks the sunlight from reaching it, and the shadows are quite a bit bigger then that in real life. Also, the moon doesn't actually glow like that.
Your grass is shaded all wrong, because you gotta consider the distance between the earth and the moon. It's hyuge. The moon reflects light from the sun back towards the earth, and it's more radial, instead of concentrated, so the entire ground would be rather evenly shaded, instead of light as focused as in your picture. Things are also way too saturated for night time.
God I hope that made sense.
Anyways, keep it up
Alright, made another example image:
It sucks because I don't have my tablet.
Sucky red ball is earth, I guess. White lines are sunlight, just there to show where the sun would be, since it emanates light in every direction, not just where the white lines go.
Red lines are what you're doing with the moon's reflection, green is what SHOULD be happening.