Week 6 - uncontrolled movements during naps

Baby boy, 6 weeks, breastfed only, normal development. He sleeps mostly ok during night time with 2-3 feeding sessions and 1-2 new diapers. However, during the day his feeding sessions are no longer 8 mins, as he fells asleep and then gets agitated (while sleeping) - jerky movements, grunting, weird noises, sometimes he even cries in his sleep. He only settles on my chest, never in his crib.

After 20-35 mins he wakes up all fussy.

Is this normal?

Why is he feeding so little?

Thank you mommas!

🙏