He probably wasn't having a freak out at all. I bred beardies a few years back and they were all very different.
Some will happily just sit around all day and do nothing whereas some will prefer to be running around and being silly.
Some days they don't eat much, some days they do. They're like us that way.
If you think about it there isn't really much to do other than bask and sleep for a beardie. If you had snakes you'd be panicking! They sit around in the same place sometimes for days/weeks on end and do absolutely nothing. Sometimes I have to poke mine to make sure they're still alive. (which they don't appreciate)
Is the strip light UV or just a normal light? Cos he does need UVB.
He is probably still adjusting to his new home too, as he gets used to the place and you he will soon come out of his shell.
If there is nothing physically wrong with him then don't worry. Hardy little buggers they are and also rather lazy at times!!
Oh and they don't need high humidity unless they are shedding. If they are, then misting helps to soften the skin and help it come off. Otherwise don't worry too much about that!