Arms flapping at 6mos old

Hi mommies and daddies! My LO is 6mos old. She is always flapping her arms, like up and down, especially yung arm na free (nakaipit ung isa sa kili-kili) lalo na pag during nursing session namin. Ganito din po ba babies nyo? Normal lang po ba ito? I scare myself googling this hahaha. Some say it’s just a form of excitement or happiness.