Many Long Post Covid Symptoms

Hi,

My name is Brian Dube, and I got Covid in September 2021. After I tested negative, I started to develop some weird side effects like insomnia and lack of appetite; I was restless, drinking a ton of water. I even had a maniac episode amount some other symptoms. I got hospitalized and recovered from those symptoms like in 7 days. However, in January 2022, all these side effects returned, but this time worse. Now insomnia it's more complex. I can only sleep (although I don't feel that my body has rested) with a combination of zolpidem 10mlg, melatonin 10mlg, and lithium 300mlg. I have been diagnosed with deep depression (I even was hospitalized in a psychiatrist), and I have a significant eating disorder. I don't feel hungry or satisfied, can't deal with stress at all. I have tremendous pressure in the back of my head, lost more than 20 pounds, extremely slow digestion, stopped sweating, constant tinnitus in my ears, amount some other symptoms.
I have done as many exams as possible, and none of them reflects any significant abnormality, anyway, the symptoms persist. So I will appreciate any direction that will help me to keep going because I do not know what else to do.