first, welcome to the boards, i hope you enjoy your time here
now, to the sprite. you have managed to avoid at least three of the classic pitfalls of new pixelers, and kudos on that. you wonrked in a manageable size, did not pillowshade, and did not rigidither. The sprite is a bit stiff, altohugh not bad for a first try. the green colors arent awefull, but trying a different palette with a broader understanding of color would probably do you good, check the rest of the forums for some very basic color concepts with regards to pixelling that i think from seeing this youll be able to grasp pretty quickly.
once again, wlecome to pixelation