I'd say, yes it does look like copper (Im assuming the top of his head isn't done yet?) And, the corrosion looks fine, it just needs to be touched on every other corner or so, but keep it balanced. (Not too much, not to little; Right now at too little)
But, it looks great overall! I cant wait to see the finished product ;u; //followsintently LOL

I think your corrosion is looking good. Add some around the edges of his mouth as well, along with a few chips and weathering for the look of "it's been used a lot". Look at more references for real copper objects too help get a feel for the lighting. I'd say it's a bit to bright on the light side, but that's me. Maybe you can add some of the copper corrosion around his eye as well?

Oooh, what is this? :)
I have an old copper kettle that I can photograph for similar lighting to your piece. I also typically think of copper as having more of a pink/coral cast to the sheen, like http://www.objectsandelements.com/shop/images/4050.jpg though a warmer light source would probably mess with that... Add in some darker areas where the copper is just starting to get to that green patina stage too, perhaps..?