I had H1N1 twice and the first time I felt like I was going to die. For an entire week I had to army crawl to the bathroom because I was too weak to stand. I understand now that I should have been hospitalized.
It can be a truly horrific infection.
Very similar experience for me in 2009 with H1N1. I had to hang upside down over the edge of the bed several times a night to be able to cough up enough to breathe, and couldn't sleep lying down for two weeks. Too weak to do anything at all. My ex coughed so hard, for so long, that he actually cracked a rib. Haven't missed a flu shot since.
Oh yeah, I used to get a flu and then opportunistic pneumonia literally every year. I've cracked so many ribs from coughing, it's just brutal.
H1N1 made me crack a rib too, but also left me feeling like I just couldn't breathe. I had never had that before except as a kid when I would get croup regularly. It felt like crushing pressure and suffocating.
ETA: I also suspect that I got covid early in 2020 before the shut downs. I was working in an extremely high exposure health profession with a largely Chinese population, many of whom had just come back from China after Christmas, right beside the nexus of our city outbreak.
I didn't so much get sick as just lose my ability to breathe properly, just like with H1N1 the first time, only without the vicious cough. For 6 straight weeks, I just couldn't breathe properly. I was so weak that I was falling asleep all the time. I sustained narcolepsy-ish symptoms for months after my lungs started working again.
It was the strangest infection I've ever had.
I got covid again this past summer after a flight, but this was after 5 vaccines. It was more like a traditional flu, except again no serious cough, more trouble breathing, but with exquisite body pain. It hurt to have the sheets touch me. That lasted about 12 days.