Son ( 5) in bed for 3 days. fever comes and goes. heart beat fast and aggressive some times. he sleeps most of the time.

Emergency Exam: Any Fever of Unknown Origin in a child that lasts this long & with these symptoms should be dealt with as a medical emergency that should be evaluated as quickly as possible at an Emergency Room. Your child could have a serious infection or some other illness & the sooner your child is properly evaluated and treated the better the chances for recovery. I hope for the best for your son!