Beardie not eating and sleeping a lot?

My beardie around a year old and is normally pretty perky. Now that the weather is getting colder and I don't have central heat in my house, he's been getting lazy and has basically stopped eating. I got him a second light to keep the heat at the right temps. The temps are around 95 daytime and 75-80 nighttime. I feed him live gut loaded vitamin dusted crickets, kale, mustard greens, carrots, and occasionally blueberries and mealworms. Lately he's been staying either in his tunnel or on his hammock sleeping and he won't eat even when we try with tongs, he backs away from it. Could it be that he's going into a semi-hibernation or could there be something else going on? Any advice would be greatly appreciated!