I did get H1N1 a few years back. The headache that came with that was a whole other level and lasted days. I was concerned it was meningitis because it lasted so long and was so severe so I actually went to the ER.
Sickest I can ever remember being and I have gotten the flu a few times in my life.
They are certainly not enjoyable. Not by any means. And why they strike is still a mystery, unfortunately. A cousin died of meningitis at a young age. The (small town)doctor was at a loss not knowing what might be going on. If one illness doesn’t get you, prepare for the next.