Viral Fever. There any test to find it?

Symptoms: Fever 102f Vomitings Cold Cough Burning while peeing Body pains Feeling very weak How i got the infection: It started with my father then spread to the entire family except my mother. Each person symptoms are slightly different I am suffering from fever(102) for the last 3days. I have taken online consultation doctor prescribed me Azithromycin, dolo 650 and montair fx for 5 days. Even after 2 days temperature not came down, if the dolo 650 tab power is up my body temperature is spiking to 102 and feeling ultra weak. So went to local doctor he prescribed me malaria, dengue, widal, covid 19 ag tests. I got through the tests they all came negative. I got covid-19 in march 2021, so local doctor thought this may be post covid effects, he prescribed me ct-scan for lungs. I got the ct-scan it came out to be clean. Can anyone tell me what is the problem, is there any test to find it?