At first I felt that I was perceiving the chaotic source of the projection that is our reality, which was interesting. This turned into a super vivid nightmare in which I went through previous points in my life in which I had in fact died and all the following memories were just imaginations made up in the moment of death. After this I regained some awareness of where I was but was convinced I had stabbed myself in the stomach for quite a while.
The dose was quite high, but I didn't feel that I had control over any of this at the time. I wouldn't trip without a sitter again (or a long playlist queued up - only had one CD which ran out).
Afterwards I noticed that other tryptamines I tried (DMT, LSD) risked flashbacks to that experience, although this could have been placebo. I have since had positive trips :)