Struggling with Chronic Symptoms After Covid

I've been struggling with a cluster of symptoms that have gotten progressively worse or more frequent ever since I had covid this past January: fatigue, swollen and tender lymph nodes, joint pain, muscle aches, low grade fevers, dysautonomia. It basically feels like I'm always coming down with the flu. Exercise makes it worse, so I haven't been able to do that like I used to. After the doctor I'd been seeing dismissed my symptoms repeatedly, I switched to an internist who ordered a bunch of tests last week. I'm hoping that something will show up to get me closer to a diagnosis so that I can figure out what is happening to me and how I can deal with it, and of course I'm really nervous that the tests won't reveal anything and I'll be back at square one. It's so frustrating to live with chronic symptoms and have no tools to manage them. Any words of encouragement out there?