Something really weird going on with 5 month old????????

My 5 month old son has sandifers syndrome which is acid reflux in a baby he's on medication which works miracles bit here's what concerns me he's a really happy baby seems to be developing fine but about once every week he's a completely different person he won't have much eye contact and won't pay attention as much he cries and seem like something hurts he wakes up with puffy eye bags and he just seems I'll the whole day ad when I say I'll I mean he looks really bad this only happens about once a week or once every two weeks hes been in observation at the hospital because of his acid reflux I've talked to doctors about this and they say it's the acid reflux but acid reflux seems totally different than this

Im trying to see if anyone can relate or had any idea of what this is or could be