I've browsed through this forum for years but am just now making a profile.
Currently 24, I've experienced POIS as long as I can remember. Mostly mental symptoms for me. Extreme fatigue, brain fog, irritability, lack of coordination, hard to process emotions. Sometimes I get a few physical symptoms like itching and chills.
In terms of when/how long I get the symptoms? Same thing every time for me. I get them immediately after O. Then, the next day, the symptoms persist. I'm always so exhausted. I don't have the motivation to do anything, which is the complete opposite of my usual self. My POIS turns me into a zombie.
I'm always relieved, however, the very next day. I wake up, and I can tell immediately I'm back to normal. All symptoms gone. This also works if I take a nap the next day after O-ing. Two sleeps after O, I'm always back.
Does anyone else experience this? It's probably also important to note that I'm Vitamin D deficient. I used to take supplements daily with that, and I definitely did see an improvement, but I've just been bad with taking them every day now.