Are you sure baby is hungry? My twins are 12days old and for the past 5days they were up every hour crying i thought they were just hungry so i kept feeding them, well i got them dr.browns bottles for fussy, gassy babies and now for two nights straight, they only get up every 3-4hrs and they eat get changed and fall right back to sleep:) get the bottles! They are amazing.
Try extra hungry formula or phone your midwife/health visitor that's what they are there for !
Breast feed the baby..if they dont get full with formula you can breastfeed him/her