Baby's poop

Goodevening po :) My baby is now 3months old, napansin ko po yung pupu niya buo po. Compress po sya pero nung tintry ko naman po siyang durugin malambot naman so I don't consider it as 'tubol' or 'sobrang matigas'. Yellow naman po yung poop niya which I think is normal. Sabi ng tita ko, need ko daw painumin ng tubig, formula po kasi siya. Pero before po siya mag poop ng ganon pinainom ko po sya ng Oregano I don't know kung may connection yon. Nakakabother po kasi :(. Any opinion po. Thank you so much.