In the last three years, something related to my gut-brain connection got fucked. I'm not sure if it was some kind of post-viral inflammation causing stress, or stress of isolation causing inflammation. But it's definitely a two way street and mine got completely stuck in a feedback loop. The mainstream medical system failed to help me. Eventually some functional medicine doctors managed to help me improve via diet, supplements, herbal remedies and probiotics. Through (risky) experimentation and happenstance I found even more relief with some traditional medicines (pure Greek mastiha sap, kambo and Ayahuasca) and anti-malarial pills I had taken for unrelated reasons.
Unfortunately the mainstream medical system has been completely unable to investigate or explain what is going on with my body, but anecdotally, the theory that there is a two way street between gut bacteria and the brain completely aligns with my experience.
I'm feeling better now, though my stomach still feels sensitive and I can no longer tolerate gluten.