If you can't get all those little hairs blacker, I think that's OK. The main difference I can see is that the top dark area over the eyeball is a lot darker in the photo. And you made the bottom dark enough, so I think you could make the top as dark. There's just the faintest lighter area in toward the nose. You made a dark rim at the bottom of the top eyelid (or whatever it is), so I think you can darken the rest of it, too.
This is another very good drawing. I think I like the puppy better because I can see the whole thing, but I understand that you want to practice eyes.
BTW, how did you make that one dark hair that comes out of the tuft of dark above the eye? That's black enough, and it's a very fine line. So you can make really dark, fine lines.
The dark black around the eyeball (and the pupil) is charcoal and yes, I can darken the area around the eyeball ok with charcoal but I'm afraid that if I try darkening the black hairs, like in the lower right, with charcoal, it will wipe out the white hairs. That one dark hair up top showed up good because the background was light so a dark graphite pencil worked fine but it's a dark gray, not black. I guess I'll just go with a charcoal pencil for the dark hairs and see what happens. It's just practice anyway.
I chose the puppy because his eyes were closed.
All I was thinking about was the eyes. I didn't think about all that shading.
So to practice an eye, I cropped one eye from a photo to practice on. I'm not ready for 2 eyes. 





