I got a memory that at 2016? winter I had a bad cold for 2 weeks, my whole throat was so sore, each time I ate food it hurt, drank lot of tea/warm water, slept in thick clothes, etc. felt odd, achy, stiff overall and I think when I Oed I recall feeling even worse, when I healed, I still felt the nausea I had while sick, even though I wasn't physically sick for a few days after I felt as I still was, it disappeared as I forgot about it, around that time is when I recall feeling bad after PMO, even if O without P and every time I did it, I thought how I must stop it (but might've had POIS before but I never was aware/paid attention to brainfog so don't recall when symptoms appeared) then I felt bit off post-O, but never abstained longer than a few days so didn't see connection till end of 2018/start of 2019 year when I had 1st big abstinence streak that I noticed post-O/WD I had symptoms, then I made the connection and read about POIS later.