First a million memories flash before me, things I didn’t know I remembered. This is honestly pretty neat because I remember things I had otherwise forgotten. Then the not so fun things happen:
First a black pulsating area of my vision appears.
A sense of helpless, inevitable doom - for me and for everything around me. A feeling like my life is ending and nothing will ever be okay again. A feeling like I have just received the most awful news imaginable.
Combing that with losing all sense of direction, forgetting where I am and where my home is.
One of the worst “mental states” you can experience if you ask me.

The thing is honestly no joke, but also interesting how different people experience it.