Formula Feeding Question - 2 month old

FTM here. Had our 8week appt today with Paed. We were giving baby every 3-4 hrs with 120ml coz we were initially told at the hospital upon discharge & also by Lactation consultant that formula fed babies should feed every 3 hours .

But today Paed tells us that the every 3 hr only applies until baby is 4weeks old & after that should only follow on demand with a max no feed limit of 5hrs. To quote , he said “He is a baby not a robot.”

We were shocked if we did something wrong & may be overfed him & so he became colicky/ gassy but the doctor said us it may not be the case.

Anyways, once we are back from hospital after the Paed visit , I notice that now (today) baby has only taken 600ml (20oz) in 24hrs & until yesterday it was around 800ml (27oz). 🤯🤯🤯

Going by Baby weight , he should be feeding 26oz per day ( 2.5oz of Formula for every Pound of baby weight)

- Is this really ok ? Quantity wise ?

- Should the feeds be on demand only for formula feeds ?

- Or could it be that he has eaten less today because of the vaccination (also running mild temp & he cried a lot)