Hi !
Abdominal pain in case of children could be very much perplexing.
Does your son have a sore throat/ other
respiratory tract infection. In such cases, both fever and abdominal pain are likely to occur specially in paediatric patients.
When was he dewormed last ? Sometimes worms do persist in the abdomen even though the
stool test may be normal. So consider deworming him on consultation with your paediatrician.
High fever could be due to any kind of infection. I have already mentioned about RTI. Other infections could be a gastro intestinal infection due to eating something outside which was not hygeinic, and also could be a
urinary tract infection which can give rise both to a high fever and abdominal pain. So one should also go for a urine test both routine/microscopic and a culture/sensitivity.
Seeing the duration of the fever and tummy aches, one more infection one has to exclude is the
enteric fever for which blood tests has to be done on advice of your doctor and accordingly the management also changes.
Over and above, you have to take special care on his diet specially with a history of
lactose intolerance.
In my opinion, you should soon see your paediatrician specially because of the high fever he is having.
Hope this helps you. I wish your son an early recovery.