my 6 years old son vaccinated 3 days back still his complain about pain and not walking properly

A. Mam didn’t you do a cold compress after the vaccination because it’s important that you do it and if you haven’t or if you have done it still if the child is complaining about pain then you should consult consult your doctor ointment which is going to be helpful and if you need to do hot compress now because it has been three days to the vaccination