6 week old baby flinging himself all day

[ThisLimeBee]

I’ve been told it’s normal but just looking to see if anyone has had any similar experiences.
My 6 week old flings his arms and legs consistently throughout the day, he will do it when he wakes up but it’s not just limited to that, he flings himself around when he eats majority of the time and will arch his back & just look uncomfortable in general.
He’s started lifting his head when he’s picked up/doing tummy time in the last few weeks but again his head flings around constantly, not sure if that’s just because he doesn’t have good head control yet.
I’ve read about infantile spasms and have been terrified, but been told that it’s unlikely that and might be related to reflux so I should go back to the doctors in the next few weeks if it continues?

Does he show any other signs of reflux @ThisLimeBee?

Yes he's sick quite a lot, sometimes during feeding but mostly afterwards. We keep him upright during feeding & burp throughout and keep him upright after feeding but he still looks so uncomfortable when he eats/after. The doctors said they can't do anything because he is still eating and gaining weight.

Is he FF @ThisLimeBee? If he is it might be worth switching to a comfort formula to see if he improves any?

Weight gain is a bit of a red herring as sometimes babies or DC with reflux or CMPA can overeat to try and seek comfort.

Yes he is FF. That's a good idea, thank you I'll look into which ones there are
I never knew that about overeating for comfort, but it makes sense as he eats "more" than the doctor said he needs for his weight & does sometimes eat without seeming particularly hungry like fussing on the bottle & throwing it out of his mouth but screaming for it back and either gulping it down or drinking tiny little bits at a time.