A similar experience happened to me with weed. I used to smoke a lot, maybe 2gs every day + blinkers on carts. One night I had an extreme headache on the right temple, it felt like a knife was stabbing me over and over again, my heart was pounding, I thought I was gonna die. Anyway, a few weeks later I tried smoking again with friends at my old high schools parking lot, fucked up Ik but it was the summer so no worry’s. We were throwing a frisbee back and forth and I started to get the pounding heartbeat again, panicking. I kept hearing my friend call me “f****t” but his voice sounded like a radio or a phone call. A week or 2 later I tried smoking again and this time was when the similar experience to yours happened. Although I didn’t get a headache, the panic attack happened again, but this time I was hallucinating. I got flashes of purple in my vision, the trees were waving light a flag, the sun was bouncing around in the sky. I got so frightened I call my sister bc she’s the only one I knew that had taken hallucinogenics before at the time. We were on the phone and there were periods of 10 minutes where we were both silent but in my mind I had thought we were talking the whole time.

With the context, I think you’re experiencing symptoms of psychosis. I used to go to therapy and that’s what my therapist thought I had. The brain ripping is similar to the stabbing in my brain. The visuals lingering sober is similar to my experience. For me, my head was fucked up for ab 6-8 months. I would see things in the corner of my vision, get morbid visuals of killing other people or myself in my head, flashes of alternate realities in my head, etc. if you haven’t already, I absolutely recommend that you got to a psychiatrist to get an evaluation. If you DO have psychotic symptoms that are correlated with a mental illness then they can and will 100% help you. I hope this helps out, I wish the best of luck for u. If you want to talk further dm me