I have been down with persistent low grade fever and sore throat including productive  cough with with white to yellow coloured sputum After taking cefixime 200 mg and Azithromycin 250 mg once a day, it went away in three days I did blood report along with malaria dengue typhoid and covid test all reports along with chest X-ray which too was normal. Only my crp levels came 42 which I assume is because fever but after week passed again I started getting fever alternate day which never crossed 100 and usually usd to be 99.6 and use to go back to normal once I take paracetamol I went to doctor spoke to him he  suggested tha me for augmentin first as augmentin develops severe weakness in me I told him to suggest other drug for which he asked me to take 5 days once a day course of cefuroxime 250 And suggested me for ers and tsh test Please let me know what can be the reason for reoccurring fever since apart from temperature I don't feel weakness or anything Which test shall I further do