Yellow is a very hard color to shade. I love the detail on this, but you should add a vertical white line, where the lighting hits the can, since it's round. Also maybe darken the parts that are away from the light. All of that would give it a more realistic, metallic look.
Thank you for advice :)
"Can Coffee 7" was made referring to your advice.
http://www.pixeljoint.com/pixelart/45066.htm