Adults chew gum, pace, etc. Everyone has ways of coping. True clinical
anxiety is a
disorder that a physician can diagnose, however, I wouldn't assume this is the case. I do believe that talking to your grandson would be helpful. While clinical DSM 4 anxiety can be treated with medication, having worked in this field for many years--- I can tell you that almost always physicians suggest "talk" therapy as well. This is an important piece of the puzzle.