Duckling question

So for those who have raised ducklings, this is my first flock of ducks. One of them is a buff Orpington Duckling. Whenever she gets over excited, she starts to lose her balance a lot and fall over repeatedly. I have to hold her for a min before she calms down and can walk normally.. I have never seen anything like it before. Anyone have any ideas?

Erica, how is your duck, and have you found an answer to your question? So sorry for the late response.