Definitely wait hun. Hungry baby milk is designed to delay the onset of early weaning, not for them to last longer. It is harder for them to digest as well, and if given at a young age will probably cause constipation.
My little one goes through stages of drinking between 9-11oz every 3 hours, it's just a growth spurt. His feeds will probably settle down in a few days and if not you have got a milky boy! My boy didnt start having 7oz till around 9 weeks!