My bearded dragon eats 40 or more medium crickets everyday. I dont know how old he/she is because I got him/her at petco. He/she was 7.5 inches when i got him/her. He's/she's 14 inches now (i got him on march 13). I dont know if he's/she's growing too slow or thats just how they grow. I dont know how much he/she weighs (oh, yeah... how do you weight them? ?). Im sorry i dont know a lot about my own beardie its just i got him at petco (dont get them from petco if you want to know how old they are or what gender they are).
Can you share some photos? They all grow at different rates, but body condition is a pretty good way to tell if they are in good shape.
Nice meaty legs, a thick base of the tail, a more "loaf" shape to the body and tail (not a triangle) and nice meaty 'pads' on the head just behind the eyes are good indications of a healthy body condition and appropriate muscle.