idk whats wrong ?!?😭

Casandra
so yeaterday 12/3 around 10 and on my baby started crying unconsolably in his sleep and then stops  it was happening often doesnt wana eat as much as he used to and now it has went down to lil wining in his sleep idk what he might have i took him to the hospital today and they said he was fine no fever  or nun ??? what can it be