I would say you're Dragon is unusual.
I would definately get a digital thermometer with a probe. When Dragons are cool their metabolism slows. This usually means they eat less and therefore poop less. A 5-6" Dragon is a baby, probably under or about 1 month old. Your should be feeding him appropriate sized crickets (1/4 - 3/8"
at least 2 times a day (I never had any luck with feeding more often than 2) If he eats 20 a day that would be good.
Calcium. I'm not sure if you're only dusting with Calcium once a week or just Vitamins. So I'll list what I would do.
You need Calcium with D3 but no phosphorous (also no Vitamin A) and you should be dusting the crickets every meal. One meal a week I would dust with Vitamins alone instead of the calcium. I would use the RepCal Calcium & Vitamins since they use Beta Caratine instead of Vitamin A.
Temperature. The hottest part of the basking spot should be 110 - 120. The backgroung temperature(air temp) should be about 85 on the hot end. The cool end should be 70-75.
You didn't say but his tank should be no smaller than a 20Gal. Long (30 x 12 x 12H) in order to have the proper temperature gradients.
Moisture. When dragons are dehydrated they have difficulty going to the bathroom. Going in the bath is normal at any age. I commonly bath them when I want them to poop. There should be a small water dish in his cage. Can be like a large bottle cap for his size. You should be giving him fresh greens everyday. Mist the greens when you put then in and throughout the day if you can. That way when he eats the greens he gets water. Many won't drink from the water dish. I also offer mine water from an eyedropper daily. You can also mist the Dragon so some water will be absorbed through the skin. Mine hated this so I stopped doing it as they got to about 12"
Sand. I would definately remove the sand right away. That's a possible disaster waiting to happen. Just use newspaper or paper towels until you get the Carpet.
Hope this helps.