im abit worried, since starting my little boy on porridge hes not been drinking as much milk he has…

im abit worried, since starting my little boy on porridge hes not been drinking as much milk he has a few spoonfuls of porridge in morning but after that he can sometimes only take 2 or 3oz im worried hes not gwtting enough food in him, the reason i started the porridge early was because hes always been a very hungry baby and he didnt like baby rice, im really worried and health visitor has stopped seeing us?