Bearded dragon acting unusual?

This morning my bearded woke up with a black beard and he hissed at me. He wouldn't eat anything when he woke up any. I read in a book that beardies are supposed to hibernate in december. Could this be the problem? This is the first winter I've had him, and I'm not certain whats happening. Help me please?
If he's full grown, I'd guess brumation (kind of approaching hibernation).

Here's a link to a great article about brumation. Also use the site for the caresheets and advice forums!
http://www.beardeddragon.org/articles/br...
Ti's is the season for them to act a little eccentric. Probably will sleep more, poop less and just black beard more then ever up to that time. Doesn't last too long. This is the 2nd winter I have had my beardie so I am not freaking out around this, neither should you.

Also, if it is kind of young, it might be going through puberty. Not fun. If he continues to hiss at you and open his mouth to be aggressive, just grab a piece of lettuce and put it in his mouth (big piece, scrutinize fingers). My breadie got a confussed look and forgot it was being aggressive when I started doing that..
Answers:    omg i asked the same thing lemme guess not intake lazy or not acting itself i add on to my answer if my cross-question gets some answers to so hold up
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