Is it normal for my baby beardie to stand on his hind legs and press against the glass of his tank?

I know my temps are right and my tank is big enough, because he is only 5 weeks old. But he still keeps running up to the glass, standing on his hind legs and pressing up against it. Sometimes, I wonder if he is seeing his reflection or something. Is this normal. Sometimes he will even do it and close his eyes. WEIRD!