Thank you for your query on Healthcare Magic,
Your child seems to have developed gastritis
due to infection or secondary due to antibiotic medication given for repeated episodes of acute gastroenteritis
Continue the medication as advised by your doctor and you can add one antiemetic like ondansetron
in prescribed dosage for the control of vomitins depending on its presence.
If the vomitings are still persisting consult your doctor for basic investigations.
Hope I have answered your query.