Did you take any other drugs?
I've experienced stuff like that at high LSD dosages, but it wasn't unpleasant. In fact, I liked it. It's what I meant by "ego death".
That is, there's no awareness that an "I" exists. There's just stuff happening. Inside, outside, all the same. Just stuff.
And then gradually, there's this internal dialog that starts talking about all the stuff. That is, consciousness, what I'm calling ego aka "I".
With marijuana during LSD peaking, that happens abruptly. With sometimes considerable anxiety.
For the most part though, my small experiments (LSD, mushrooms, DMT) have had a very positive and borderline revolutional effect on my outlook on life. Only time I've had negative experiences have been on mushrooms, both LSD and DMT have always been positive.