5 month old arching back

[Mybooboo]

Hi. Just looking for a bit of advice as the internet make anything sound very serious.
My little one is 5 and a half month old. Happy little baba although a very bad sleeper.

He has just started arching his back if I try and hold him sideways. ( hes breastfed and used to sleep in my arms all the time) after food or even up to an hour after or just anytime really. Spoken with the pediatrician and got told to wait a while before they can diagnose if its reflux ( he had it when he was younger) but I thought he'd grow out of it by now. The internet search immediately gave me cerebral palsy and that freaked me out.

He also kicks like theres no tomorrow especially in his sleep. I've never seen any baby do that either. He moves so so much. Is this normal?
Does your little one arch his/her back? Or move so much in their sleep. Just looking for some peace of mind .

TIA

Sounds normal to me. I've had 3 and nannied 2 of that age and 3 of them would do the arched back. One of mine used to move so much in her sleep that she'd often be found wrong was round or sideways in the cot. It wasn't even as though she slept long either

My son did but also screamed a lot and he was diagnosed with reflux.

Is say normal too, please don't listen to Dr Google. I've had to stop watching my 4 month old in the monitor at night. Since putting him on his cot he's become a huge fidget. He looks like a child possessed with how much he moves around, the amount of movement is mental.

Thanks 🙏 I'm glad to hear I'm not the only one

Have you considered milk allergy?

Hello
Does your little one still suffer from arching back? My little boy is 5months and has started doing this a lot more lately - during a feed.