Talk to Gastroenterologist on Stomach Ache And Fever

my child eat red beans at night, in morning around 11 he started crying due to stomach ache for at least 20 min after that he vomit and slept. till night after every hour or 2 he complains about stomach ache and sleep after that he also had fever doctor prescribed 1.tinocef 2.febrol 3.spasler-p 4.domel he got better NXT day eat his meal NXT day again complain about his stomach ache catch fever of 102°F got drip to lower his fever. next day he 1-2 Tim said his stomach ache but not severe but now at night he has fever kindly tell me how to treat him?