Upside Down Feeding....or Not.

This little guy must be hungry because there's obviously nothing in the suet holder and yet there he hangs upside down picking away.  Soon afterwords there was a new cake present but he wasn't around.  This appears to me to be a small or young woodpecker.  It has all the markings on the wings and head of the red headed one that showed up shortly after the new cake went in minus the red head markings, but then I'm not knowledgable all that much on birds.