Don't worry , sometimes it happens !!
With the vaccine did he take any medicine for fever ?! Please mention any allergies or medical conditions like High BP ,
Diabetes and is he taking any medication.
Next Steps
If didn't took any medications then take tab.Dolo 650 mg.
take tab FSFA once a daily
tab MVBC once a daily
tab shelcal 500mg once daily for 1 month
Health Tips
get tested (CBC) after 1 month.
Take proper diet rich in iron Exp.(beetroot, dates, etc).