@Img_9999, thanks for sharing that, I love that report and identify so much with so many aspects of it, for sure I've felt very similar things on tryptamine+disso combinations, that feeling of...
Dissos obviously are notorious for teasing some kind of secret truth about reality but combined with the somehow more "real" feeling holiness of a tryptamine it really brings this feeling into sharp focus. I've never actually combined a heavy hole dose of ketamine with a 4-sub-trypt, partially because I only snort and usually in the depths of a trip snorting a large quantity of powder often seems like a less than pleasant idea, but your experience really reminds me of a 4-HO-MET and 3-HO-PCP trip I had, specifically...
Although on my own trip it was significantly more ego-tinged than yours appears to be, in that I believed that I was actually capital G God him/her/itself and the progenitor of the entire universe - that space without gravity is a place that I feel like I have known.
While I was there - or, actually, maybe shortly after in a more difficult part of the experience, which I characterised as "closing the loop" of existence, suddenly "remembering" that in fact, there is only this experience of being, but this experience actually makes up the infinite kaleidoscope of fractal conscious sensations - but, usually, "we" only experience one piece of it a time, as the differentiated units of human consciousness that we are... I acquired the belief that every unit of consciousness will pass through this vortex which is the intersecting central point of all existence, when we momentarily remember what we are, that we are all one, before "forgetting" once more. From what you said it sounds (to me) like we visited the same place, if from different directions, and via different methods, but obviously we've both forgotten the experience of what it is to be the other, or indeed, to be anyone else at all except ourselves.

Not that dissos+tryptamines are the only way to visit this place for sure, but it does seem to me like the specific framing of these substances lends itself to a consistency of experience which makes what is, essentially, an experience outside the realm of human comprehension, into something that can be somewhat consistently explained, if not entirely understood.
I get this totally and I had the same thoughts after my own experience. The way I framed it to myself was that - essentially - yes, it was a drug induced delusion, yes, it was a period of temporary insanity and in that sense not literally "real" in the way that we usually speak about whatever "reality" is... and I think it is somewhat important to keep this perspective to give oneself a little psychological distance from such an experience, so as not to lose the ability to function properly in everyday waking reality or open the door to more serious delusions. But, equally, my own perspective was that the experience was representative of something real - in that the boundaries between our individual consciousnesses and indeed the very human concept of an individual self are all, ultimately, illusions, and small parts of a "Greater Reality" which remains outside the realm of language, the comprehensive abilities of our messy biological brains, and indeed probably outside time and space as we understand them from our very limited perspective.