Amount🤷‍♀️

My little one has just turned a month old currently doing 90ml every two hours sometimes will go three/four at nighttime, when should I be thinking about upping his milk to 120ml? If I do this am I right in thinking he should go three/four hours between instead of the two he is doing? Sorry ftm here and worry il give him to much/little🤷‍♀️

Just to add he is still quite small and fitting in newborn clothes☺️.