Thank you for your query,
The cause of his feeling of unwell may be due to the diarrhea
which causing some abdominal discomfort.
Try to give plenty of oral fluids and oral rehydration solutions, coconut water.
Watch is activity and urine output.
Examine his stool whether the loose motions are continuing.
Consult your Pediatrician
for the assessment and proper management advise.
Hope I have answered your query.