My baby poops once a week

Ask ko lang po mommies, pure breastfeed po baby ko, 1month and 28 days na po sya, okay lang po ba na once a week sya magpoop ever since nag 1month sya? Tsaka pinainom po sya ng byenan ko ng distilled water kasi sabi ng isang doctor na okay lang daw para magpoop sya more often pero talagang once a week lang po sya magpoop