awww, she's really cute! i like the blinking animation too, nice and smooth.

i would recommend trying to adjust your colors for more contrast, though. use a darker grey to shade her outfit, a darker brown (try desaturated red tones!) for her hair, etc. the shading is hard to see, especially on the hair, because the colors are so similar to each other. try using darker colors for shading on your next piece and don't be afraid to have the colors stand out from each other. don't be afraid to shade stuff with weird colors, too - like a greyish blue shading white, or the aforementioned dark grey-red on brown hair, etc.

doing studies of the shading techniques of artists you really like helps me, too. find a really good pixel artist that you admire the work of and zoom in really close on their piece. take note of the colors used and how they contrast and try to imitate some of the techniques they used and ask yourself why they used them and why they work in this instance. doing studies is a great way to help your art and learn new things.