I had all the listed symptoms including headache, fever, sore throat, muscle ache, and diarrhea, but those were all pretty mild compared to other illnesses I've experienced in the past, like the flu or even a bad cold. The one symptom that was unlike anything else I've ever experienced was the shortness of breath. There was a period of several days where it felt like I was at several miles' altitude. When I was being sedentary I was OK, but I was noticeably not getting enough oxygen even just while walking around my apartment, like I couldn't catch my breath or suck down enough oxygen.

I've since mostly recovered, but my lungs are still giving me problems (this is apparently expected; it can take months to recover from severe pneumonia, so I'm doing better than that at least). I haven't gone running in over a month whereas I used to go several times a week, and even stuff like playing Beat Saber has kicked my ass. Ironically, wearing masks is hard for me now because they interfere with how much oxygen you can take in, so I can wear them while walking leisurely, but I start walking faster, or try to carry a heavy load (groceries), or climb stairs with a mask on, then I really start feeling shitty. So I haven't been wearing a mask while outside and only don one for being inside stores (which is fine, it's been way more than 14 days since I last experienced any symptoms of infection).

So yeah, a weird illness, quite different from the usual human viruses like the cold flu that we all know and "love". I don't know if I have any tips other than don't expect to get better from it quickly (you don't bounce back in a few days like you would from the cold), and lying prone helps you breathe better (but I fortunately never got serious enough to the point where I was struggling to breathe even while being sedentary; it was only after activity). Oh, and if you do anything like smoke or vape (I don't), quit that right now. You want your lungs to be in the best possible condition before going into this because you're gonna lose a lot of capacity and if that puts you below the level required to sustain your basic sedentary metabolism, you could die, or at the least require supplementary oxygen in a hospital. Heck, take up running or some similarly aerobic activity now if you haven't already; that'll help.