I don't claim to be the definitive authority on this, as I'm not an expert in pixel art, anatomy, or anime. I'm only pointing out what confused me as a simple viewer.

1) The hand. Specifically, the palm of the right hand. Try holding a bottle like that, and you'll see what I mean. The grip looks unnatural.

2) The pants. The folds look symmetrical and a little odd. It seems like the pants are hiding something other than just the legs.

3) The shadow. I understand why it's needed in this case (I assume to separate the character from the background), but I don't quite understand the logic behind the light scattering. If the light source is close to the character, the character should be lit differently. If the light source is far away, there are no issues with the character's lighting, but I do have concerns about the shadow itself. It should be softer and a little more blurred.

Otherwise, I think the art is good. The breast and the parrot turned out great. Maybe next time you'll draw a parrot with breast? (Just kidding.)