4 yo boy jerking of arms

My son is 4 years old and recently began jerking his arms at most random times. Some days he does it many times. Other days nothing. My other son's PT says it looks involuntary. I am unsure if it is a tic, tourettes, or seizure of some kind. It definitely is not voluntarily done. My older brother has tourettes. Hence, why I am concerned. When my son does this random jerking/spasm, it usually ahows up when he gets excited or at a time he gets worked up from physical activity. He looks as though he is punching the air sometimes and his arms and neck stiffen, his eyes either shut, squint, or roll back for a split second. It almost looks like he is having a cold chill that lasts 3 seconds and has probably 3 in a row. He also makes a sound when he does this, sounds like when you try to squirt out an almost empty keychup bottle (best example I could think of) or like tongue against roof of mouth making a spitting type sound.Any advice?