It looks awsome. :-D I'm assuming that you drew this using a photo reference, and if not I would highly recommend doing so especially when it comes to drawing realistic or semi-realistic things. When drawing from a reference, I would recommend breaking the photo down into basic shapes and then redrawing those basic shapes and then going in and adding details. See More It makes capturing an image a lot more digestible and improves accuracy. I made this little sketch thing of how I would go about drawing an eye with this method. Its not particularly polished and rather scratchy, but hopefully it'll help. :-) https://cdn1.imggmi.com/uploads/2019/5/30/6131690f3a8f4c8929df10bf11224e8f-full.png
https://cdn1.imggmi.com/uploads/2019/5/30/6131690f3a8f4c8929df10bf11224e8f-full.png