So Rocco started this a few days ago where he just starts moving his arm up and down. I've gotten in the way a few times and it hurts! Lol sometimes he does it with a toy in his hand. Sometimes it's just like he's smacking an imaginary drum or something. it's just an up and down motion with his right arm. I'm just paranoid because my nephew is autistic and I know repetitive motions are a sign. Does anyone elses' baby do this??