I mean this in the kindest way possible, but your post here reminds me of a variety of other posts over the years by people who are experiencing obsessive anxious thoughts about their health, otherwise known as hypochondriacs. The best possible advice anyone here can give you is to go to a doctor. It makes no sense to me why you would assume you have a rare brain disease without having been to a doctor. I am 95% sure that there is nothing wrong with you except that you're experiencing obsessive-compulsive thoughts related to your health. If you do not get these thoughts under control, it will have severe ramification on your actual mental health, leading to anxiety disorders, OCD, depression, even depersonalization/derealization... and it's all because of the way you choose to think about things. Seriously, go to a doctor. Once the doctor tells you you're fine (or hey, maybe you aren't and I'm wrong, but then you'll know for sure and be able to treat it under trained medical supervision), if you still find yourself obsessively thinking about this, it's time to go see a therapist/psychiatrist because obsessive/intrusive thoughts can be extremely disrupting and negative to a person's life. Good luck.
And STOP reading shit on the Internet, it's the number one way to freak yourself out, and it's doing no good. You cannot possibly diagnose a brain condition by reading the Internet. And all the other people who are compulsively speculating about this are going to convince you that there's something there. Seriously, this obsessive worrying about mental conditions after psychedelics with no real basis is a thing that happens, we get people doing this with regularity here, and it happens elsewhere too. They all feed into each others' neuroses and make it seem like they're correct, it's basically a big, very unhealthy echo chamber. I'll say again, make an appointment and go to a doctor, the Internet cannot get you any closer to the truth.
I hope you don't find this harsh, I'm trying to be as helpful as I can. I've seen this pattern over and over and I can assure you that the path you're taking with your thoughts here is not healthy.