It's been nearly a week since this experience and some pretty amazing things have occurred. Since '96 (when I developed pretty strong HPPD symptoms) I have experienced varying degrees of derealisation. I thought I'd conquered this around 2001, and whilst my baseline felt altered and I still saw visual effects, I figured this would be as good as it gets, and I carried on with life.
Since this DXM experience, I realised I was still far off baseline for all these years, I can finally see this because now I feel absolutely grounded! It's pretty amazing. In the days after the experience, I worked through a lot of baggage and realised I had been focusing on reality in a perspective akin to tunnel vision with the visual effects of HPPD as the centrepiece. I basically ignored everything but the emotional feel of my day-to-day existence and was still far removed in a depersonalised sense. I now see that the day to day interactions remain the same, "I" remain the same, my interaction remains the same, and my perspective has pulled back so I'm not so blinded. In short, I'd been pretty much fucking up my own perception of reality without realising it.
This sounds basic, but the realisation is on a fundamental level which has actually altered how I experience reality on a day-to-day basis. I actually feel as grounded as I did prior to my HPPD. I feel pretty fucking awesome to be honest!
I've existed in a limbo for nearly 16 years, "waiting" when I didn't realise I was actually. This stuff (DXM) can be pretty magical.
To be honest, I'm not sure. Most of two bottles, it felt very 3P from descriptions I've read.
It's 4 days since this experience and I feel more grounded than I have in years.