Frequently fever comes. Serious problem?

Dear doctor, My son is 1 year 2 month old. His weight is 11.2kg... in this month 4th time fever come.. 1st time doc told me to give pacimol 1.6ml...within 3 days he was fine but again after 10 days he was suffering from throat infection...he gets infected because at that time my husband also suffers the same ..again told given me pacimol, alcof syrup...now again after 1 week he gets fever around 102 deg .. this time doc gives antibiotics but due to this he started suffering from loose motions..doc told us to stop ..now again this week fever comes around 100deg. M veymuch worried now ..pls help me in urgent basis🙏 m not understanding what to do ..is it serious problem? He is eating,urine output is 5-6 times,he is active ..but only at night when fever comes he doesn't sleep well .pls help me what to do