When my boyfriend's bearded dragon became impacted from sand, we removed the sand and started using repti-carpet because we care about his life, not the look of the viv.. regardless, he ended up prolapsing, and dying from complications from sand impaction. He could no longer digest his food because the sand in his system was causing him so much physical pain.
When we removed the sand, we found old poop stuck to the bottom of the viv, dead rotting crickets underneath, and hardened piles of sand that had formed around the urate that was also stuck to the bottom. It was smelly and disgusting.
Once the sand was gone, so was the smell. The putrid stench that emanated from his viv when sand was in it was completely eliminated once we started using repti-carpet.
Beardies are silent sufferers.. you may think that they are "happy", but once they start getting lethargic, stop pooping and start throwing up, it's already too late. I personally find it abusive to a beardie to have it live on a substrate it can ingest so it will be in pain while trying to force rocks out of its intestines.
I am adamantly against sand, and flat out refuse to believe it is safe or sanitary after having a dragon collapse in pain in my hands and stop breathing for several seconds because pooping was so painful for him.
Your beardie acting strange because the change in sand to a safer substrate such as tile or repti-carpet is called relocation stress. They do that whenever something is changed in their viv.
Our beardies are captive raised without being exposed to predators or deadly diseases.. they are our pets and they are not meant for wild conditions.. even so, they do not live on sand in the wild.. they live on hard packed clay and dirt. It is our duty to keep them safe. Sand is not safe.. I don't know what else to say to convince anyone not to use it, and I don't believe anything that the minimum wage earning pet shop teenagers say to convince me otherwise.