Green hair. One of the funner hair colors because it's so weird the more you keep thinking about it. At least, that's how I see green hair
Kinda hard to see if you got her hair color right though... But I notice the owner of this OC has multiple deviations of this OC with her hair ranging from aquas to chartreuse. We could probably have borrowed the really warm chartreuse from some of her works. This particular shade feels a bit lifeless. It feels like a cooler shade of green but other colors used here are a lot warmer.
I'm probably not much with critiqing human anatomy at this point, but I think it's a bit silly to see no feet, but hands.
I have a very strong hunch that you can achieve much smoother results with your pixel art though. It takes quite a bit of technical knowledge.
There are a lot of sharp corners making this work look more rough than necessary, but that can be avoided if we applied a bit of antialiasing. AA is pretty tricky to use on lines though.
Then, there are other things like banding that does make your work a bit rougher from not being too careful placing your pixels (explained here, albiet may or may not be explained as best: [link]). There's also a bit of pillow shading. A lot of your hair is shaded by darkening around the edges. This could suggest a light source from the direction of the viewer, this sort of shading isn't always accurate for frontal light sources. Chances are you'll have something more convincing if you darken only one edge.
I find it interesting on how you fattened the white outer color, but I feel as though it may be better if we never had that white outer layer of outline. If it's there to help make your subject pop out, we could just draw this over dA's background color but erase the background color later when we're done.
But, pixels being a medium with a ton of gruntwork, I'm sure we'll have even awesomer results than what we already have with more technical skill.
Thank you very much for this helpful critique~ c:
I will definitely try to transfer your advice in my way of pixeling. Actually, I am quite a beginner in doing 150x150px pixel (hope there will be much room for improvement though) so your critique will really help me to spot the mistakes and weaknesses of my work
As for the human anatomy: I am not really good either ^^" This is just the way I am drawing chibis which are easilier manageable for me than the more realistic ones.