advice ; my son is 1w and 5days constipated help

my newborn is currently 1w 5days old he tries to poop and cries because it hurts him . yesterday he passed some that was bigger than his tiny little butt i felt so bad . i have mommy bliss gripe water . is that good to soften his stool if not what is. i wanna cry everytime he tries to poop . just cause he look like hes in pain .