He may just like your hand. Although I have no experience with it symptoms of MBD are usually uncontrolled limb movement, and shaking or twitching of other body parts. From what you describe it does not sound like MBD. If it is warm enough, it would be best to keep bringing him outside for a couple hours. The sun has potent healing powers on them.
His stunted growth could very well be due to parasites if he has had them for a long time.
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How often do you feed him?
Here is a list of the best foods for a bearded dragon:
http://blackninjakitty.com/herps/care/troystuttlegreeniglist.htm
While the veggies you have been feeding him are okay for him, it would be best if he has access to at least one dark, leafy "staple" vegetable. Getting one of the "staple greens" in the list I have linked would be far more beneficial as it contains a lot more calcium than cucumbers. (Cucumbers literally have no nutritional content, they contain insignificant levels of calcium in addition to this. They are just water.)
Alternatively, you could buy a calcium supplement (which I highly recommend) so that you can dust some of his crickets with it. In my opinion this is the best way to get sufficient levels of calcium in their bodies.
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Its great that you are finding out the temperatures of the tank, bearded dragons are very sensitive to the level of heat they have access to. It really makes a huge difference having accurate temperatures. Make sure you get a thermometer with a probe and leave it on the spot you want to measure for 45-60min to get an accurate reading. The stick on and dial thermometers have been tested on this site to be up to 20f off.
- Best of luck -
