Jerky / Uncoordinated Movements

I am a FTM with a 14 week old. Pretty much since around a month old, she has CONSTANTLY been moving. And I mean constantly, unless she is ready for a nap and is showing sleepy cues. People comment on it all the time, and I guess this is what has lead me to write this post because the comments have naturally made me a bit worried.

When she’s on her back, she is pretty much constantly flailing her arms around and kicking her legs quickly. The movements are really quite uncoordinated and jerky. She stops when we pick her up and she doesn’t do it in her sleep. She does it more when she’s been stimulated (someone is talking to her, smiling at her, etc). She’s met all milestones so far, though she’s not great at propping herself up with her arms during tummy time. Guess I’m just wondering if this is a normal thing for her age as she is my first child. I plan to bring it up with her pediatrician at her 4 month appointment, but in the meantime just curious if others have had their babies do this.