Well, the thing that immediately springs to mind when I look at this is how high her hair seems to rise up from her head. Seems to me it should rise up half the distance it does, or perhaps just a little more. That'd probably mean that her hair couldn't be combed as far off to the sides, and that'd be fine too.

Secondly,what looks a little odd to me is how her hair doesn't seem affected by the fact that she's laying on it. It's much too flat. The hair should puff back up as it comes out from under her, obscuring maybe half an inch of the portion of her body laying on it.

I'm liking the attention to detail you put on her surroundings. Most people overlook the background, but it looks like you spent just as much time on it as you did on her. Nice.

Finally, her chest seems a little large, but I'm not complaining. Lol.