Hello,
Thanks for posting your query.
Vomiting and abdominal cramps with fever usually suggest a gastroenteritis . It may usually be followed by foul smelling diarrhea .
The most important precaution you can take as of now is to maintain his hydration .
Give him plenty of water and home available fluids or oral rehydration solution alternatively.
The symptomatic treatment includes antiemetic like domeperidone or ondansetron if vomiting is persistent , antipyretic analgesic like acetaminophen or mefenamic acid or dicyclomine for fever and pain respectively.
The specific treatment requires a clinical evaluation by his pediatrician for confirmation of diagnosis .The doctor after examining your child and if necessary ordering investigation like stool routine examination , complete blood counts, etc can come to the conclusion of an exact diagnosis. If the diagnosis is an infective gastroenteritis then he might start antibiotics in addition to the supportive treatment .
If he suspects viral illness which usually resolves on its own then he might just give symptomatic treatment .
Since its already two days since the start of his complaints it's advisable to seek prompt consultation by appointment as further delay may worsen his symptoms.
If he develops any new symptom like decreased urination , high grade fever , blood in stools , fast breathing , refusal to feeds etc then please seek an urgent facility . Otherwise if he is feeding well and hydration is maintained , you need not worry and might wait for routine consultation .
Hope I have answered your query.
I'll be available for any follow up queries.
Regards

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