I'm glad you got a test done, if for nothing else as peace of mind. What are his temps? If he's not basking and he's digging he may very well be too hot. Care guides can give you a good recommended base line, but every animal is different. Just like some people prefer cold weather and some prefer hot, he may like thing at the bottom of the spectrum. Try cooling things down a bit, and see if anything changes. Just make sure it isn't too cold.
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