He has started doing this in the last week or so. It's not only when he's worked himself up into a real paddy; he starts shaking, going red in the face and clenched jaw, the very instant he decides he wants something he can't reach / wants attention, etc. It almost looks like he's having a fit. Sometimes he shakes with excitement too, but it's much more often with frustration. I know it's normal for toddlers this age to get very easily frustrated but is it normal to take it to this extreme?