Girls, maybe someone knows? My daughter is 3.5 months old. I've starte…

Girls, maybe someone knows? My daughter is 3.5 months old. I've started noticing that after a sudden awakening and only during the day she gets all shaky. It lasts about 5-10 seconds until I pick her up or give her a breastfeed. The baby is healthy, active. Maybe someone had this too? Heart tells me everything is okay. Hope it will be like this. Thanks in advance.