Can U Explain Dose Of Ibigesic For My Son Fever

Can u explain dose of ibigesic for my son fever came in after with in one hour the temp gone tov101.5 . That time I have given calpol syrup the time is 3:30pm but the fever not came control after 5hrs again I have given calpol but also there is no solution after one hour I have given ibigesic now the fever came control pls explain