I had pneumonia last month.
I was bed ridden for 2 weeks.
Only been out of bed about 3-4 weeks now.
They figure I had some sort of "walking pneumonia" for about a month but really didn't know it.
I just felt tired, had a cough, run down, thought maybe I was not sleeping enough, working too hard etc.
Then in the space of 2 or 3 days I started to have a terrible cough, chunks of stuff coming up, burning chest and throat, blood etc.
My Wife took me to my Doc who immediately sent me to hospital.
X-Rays showed pneumonia.
A few hours in hospital and they made the assessment that with anti-biotics puffers, inhalers, and the fact that I had IVs going while I waited I would be allowed to go home instead of be admitted as my Wife was off work and could watch over me and report back if anything went sideways.
For 2 weeks I slept about 20+ hours a day, took pills and puffers 6X a day and that was pretty much all I woke up for.
It happens, it comes on quick.