But what the fuck IS a "reptile" experience? Can someone please bother to actually DESCRIBE IN WORDS what the hell you are talking about? Jesus H. Christ!
I've had this on 5-MeO-DiPT + ketamine. I just felt like a much lower organism, working very simply focussing on direct experience and bodily desires but with a really particular reptilian feeling. That's the best I can do, sorry, but it was very distinct for me and the word suits it better than any other one I can think of.
There might be a basis for this: the limbic system comprises of the R-complex or reptilian brain among other things and it is heavily associated with raw emotions and body language. This and other parts seem to be heritage from earlier evolutionary stages, I wouldn't dream of suggesting that other parts would be shut down by certain drugs but being overruled or dominated seems possible. I even think it happens often enough that people are dominated by these (behavioral and experiential) systems without any drug being applied.
But of course they may not have anything to do with one another. However it may be, some psychedelic phenomena get a term coined for them and some of them I can relate to. Hopefully that's enough of an answer for you.
More on-topic: yeah DMT can be incredibly overwhelming, it is more neutral than negative since often enough I find being stunned positive, like being petrified by beauty. But occasionally it can really shake me up, though I never felt traumatized by it.
If the dose is high enough and the experience negative enough it is possible though. I have read accounts of 5-MeO-DMT experiences that were so profound that people got nightmares for years after that, too afraid to go to sleep. With DMT the same might happen if you dose very high and come at it recklessly and unprepared.
Unwanted life-changing effects... that is what erowid lists for a lot of psychedelics. And yeah, it's not impossible.
This seems to be a rare occurrence so I don't mean to scare anybody with this at all, just suggest that you treat it with respect and dose appropriately. Other than that try to relax and let it wash over you and it will all be okay.
