Better change doctor, 仁安 the doctors there not so good. Infants cannot have high fever for more than 3 days and your case, doctor yet to identify source so better change for another doctor and bring your medicine to the new doctor to check cause.
I suspect glandular fever, ie an infectious disease in which one has a fever and the lymph glands swell up and which makes one feel weak for some time afterwards. Better ask the doctor to check carefully the lymph node at throat. Cheers