Nature one brand and constipation

Any mummies giving their newborn Nature one premium? My 23days old newborn is having difficult time to poo, his stools are so hard like pebble like kind. Gave him biogaia probiotic drops & it only improves abit. He is still having hard time to poo & must have the help of me helping him to lift his butt up then he can poo. The front part of his poo is now like clay like and ending part looks more normal of how a normal poo suppose to be. Sorry for the unglam photo!