feeding newborns question

Hi everyone. I have a 3 week old baby boy who is currently about 10lbs (he is due to be weighted again soon so I don't know his exact weight) and he is fed on cow and gate newborn milk - the stuff that's already made and you just pour into a sterile bottle. He has between 80 and 125mls (3-5oz) every 2-4 hours. I am thinking about putting him on 'hungry baby' milk as I don't feel he should be waking for, for example, 70mls of milk after sleeping for an hour and a half after having 130mls of milk.... I just wanted people's thoughts on this or any advice, as I am very new to this baby malarkey!