How old is your Dragon? How big is he?
MY opinion is that Brumation is likely. Here's my observations of my Dragons.
Every dragon seems to have a different idea about it. I have one that stopped eating completely on Nov. 5th. She dug all over her tank, tried various spots for a few days and then finally dug herself under a 1/2 log on the cool side. She's been there since about Nov. 20th.
All of mine have had recent fecals. I wake her up every 3 weeks and give her water, bath her, and weigh her. Some may disagree with waking her. But, after 3 weeks of not seeing her I just have to check on her well being. She has lost almost no weight in the 2 1/2 months since she ate last.
Another of mine, a male, hides for up to a week and doesn't eat. But I can see that he is awake. I put salad in his tank every day and will feed him crickets when he comes out. Otherwise I don't disturb him.
Another female occasionally hides (again awake) for a day here and there but for the most part is around and eating.
The moral of the story is:
I have fecal's done twice a year. The last being in Oct. I weigh mine regularly. Each tank has a hide (1/2 log) on the hot and on the cool side. I have about 2" of sand.
This way I know their healthy and they can do whatever they think is right for them. They can hide, dig in, whatever. Weighing your dragon can really give piece of mind. A sick dragon may not eat but loses weight very rapidly. A healthy dragon loses very little weight when not active.