Covid like symptoms but RT PCR negative.

I have symptoms like mild fever (100 or less), random sense of taste and smell (feeling different taste and smell than actual and sometimes not even a smell or taste) and bitter mouth and lips, slight uneasiness in breathing, and sore throat with light pain (feels relieved with warm water gargle for some time). Also too mush sneezing initially with slight water through nose. I am also feeling very tired all the time since 3 days. Tested for Covid (RT PCR) and the report is negative. Already taking following medicines from last 2 days: Augmentin 625 duo Limcee 500 Calpol 500 Alergin-L Bonshine I have sinusitis and thought initially that it is the cause of the problem but it feels different and I don't have any headache or blocked nose. I kept myself in hime isolation. Symptoms are still there except sneezing. Please advise.