Enough nutrients? Please help

My LO is 15 days old and he is constantly latched if he’s not sleeping. I don’t think it’s cluster feeding because its literally all day and night. He is never content, he cries once I set him down from being on the breast. I gave him a bottle of breast milk with 2.5 oz and it still wasn’t enough and he latched on for an hour. I’m his human pacifier. Even during the night if he’s not latched he’s not sleeping. I’ve tried a pacifier(different brands) and he won’t take them. Can it be that my breastmilk doesn’t have enough nutrients in it?