Hey, that's pretty good..I think he needs some eyebrows though, it looks a little strange and I think that might be why. ^^ Plus his head seems perhaps a bit overly big compared to his body.
But yeah I think it's mostly the eyes..
Here, I had a little go in Photoshop just to demonstrate how I think the eyes should be. I made the first line at the top of the eye a little thicker, then drew another to represent the eyelid. Then the eyebrows above. I'm not saying it shoud be EXACTLY like that of course, but that's just to give an idea. ^_^
The nose maybe seems a little long too, normally in anime style they would use a smaller line..but that could just be the style and it really depends on your style. =) I like the shading and I look forward to seeing some more of your art!