I have a baby that will be a year old on Thursday. She started walking at 8 months and was running by 10. She seems to be fine mentally and developmentally, but lately she has been worrying my husband and I because she will run really fast and shake her arms and head back and forth, kinda like a really weird dance, but a large part of her body is moving, and then fall. Then once she falls, she cries. Is that part of the age?