I cough really hard and phlegm is thick. What is the curative measure?

Hi doctor.

I got sick two weeks ago. I had temperature, cough, running nose. After a week, I got neuralgia. I had a sharp pain near the heart and tested for corona. It was negative. After 3 days, my throat started to hurt. I also had belly pain, loss of appetite, weakness, and nausea. Now I am getting better with weakness. I just want to ask, what to do if my throat really hurts badly when swallowing, just on one side of inner mouth. Pain also is spreaded to ear and my upper neck where is lymphnodes. It started one week ago and its worsening . I also had really bad mouth taste, especially when eating or drinking, but now its getting better. I was using probiotics because my belly hurt and i had loss of appetite. Now i bought special liquid for gargling and lozenges for throat inflammarion but it doesnt help. I cough really hard, my saliva and phlegm really thick. Im just really worried and just asking for help and how to treat it. Thank you.