My bearded dragon has leg tremors. I took him to the vet. He took blood the results are normal. What could be causing the tremors? ?

He is 7 months old in a 40 gallon tank, zoo med basking bulb 150watts, zoomed night buld 100watts, & a uvb bulb 10.0. He has a piece of driftwood in his tank, ceramic house & a hammock along with some silk plants. The green cage liner mats as "substrate". Cage gets cleaned 1 a week. His diet consist of collard greens, kale, endives, cabbage, every few days I'll mix in carrots. He gets kale daily with the other greens mixed in. Once or twice a month he will get fruit such as pear, strawberrie, raspberries, & blueberries. Wax worms I ussually mix in with the salad. I tried to incorporate healthier insects to his diet such as Phoenix worms, hornworms &butterworms but he has a very hard time digesting them, so I ussually just stick with the waxworms & occasionally feed some crickets. Wax worms I coat with calcium+d3 & once every two weeks with the multivitamin powder. His cool side is 82°f while his hot side is 105°f, the humidity is in the desert region. He hates water when placed in the water he throws himself around the tub like a child, so he gets 2 baths a month for about 15-20 minutes, warm water treated with reptisafe. He goes outside of the cage every day weather it's just to hang out on my shoulder or to run around he ussually spends about 30-40 minutes outside of the cage, I'm now decreasing the time he spends to about 15-20 minutes bc of colder weather. Is there anything I'm doing wrong to cause the tremor or is it a possibility he has a neurological disorder?