I'd always advise folks to be with someone more experience their first time. Just in case. And be knowledgeable about the range of experiences before taking. Once one has a bit of experience, being in public isn't so bad if it is timed right.
I went to see Weird Al coming down from LSD. It was nice.
I had a wonderful talk with a homeless Romanian dude in Amsterdam coming down from truffles sold there. Between the lights of the building at night, being on a vacation without my spouse, and everything combined it was pretty neat. But I'm pretty relaxed and didn't have much to really worry about as most of this was planned (minus the discussion). It isn't really much different than keeping yourself safe while cooking on psychedelics (yes, I've done this stuff).
Note, this mentions coming down - things get increasingly safer after you've peaked and are coming down. Dosage also plays a part in this: You don't have to completely lose touch with reality completely to loosen up your mind or have fun with the drug.
https://erowid.org/chemicals/ketamine/ketamine_dose.shtml says that 100-250mg produces "the K hole" (depends on body weight) so 500mg over a fairly short period sounds like quite the dosage. That you felt only a mild alteration suggests that either you have quite the tolerance for substances or that what you tried was not in fact ketamine. Also, it appears to me that you're deploying clinical language to mask recreational drug use which could be for our benefit or yours, I can't tell which.
also: i can't confirm if it was or wasn't actually ketamine. but i know that I experienced something, just nothing significant. I believe many dissociatives present a cross tolerance with each other and I was heavily tolerant to dxm at the time from heavy usage, so that may possibly have contributed to my tolerance, along with a certain level of inherent tolerance that my mind and physiology express when it comes to mind altering substances. which, and forgive me for sort of changing the topic, but that just sucks
I've been sober for over a year, and it's now amazing to me how completely terrible my self-perception was. I was laser-focused on measuring my mood and focus and completely blind to my intensely addictive substance use. I made a lot of dangerous choices. The same substances that can heal in small doses are recreational in large ones, and it takes a lot of self control to stay on the right side of the line.
I have had a lot of experience with psychedelics, stimulants, cannabis, and dissociatives. I respect the substances and value my experiences greatly. I believe there is no bad drug, just bad uses of drugs.
Here is a message I wrote to The Listserve in the middle of my using: https://thelistservearchive.com/2016/03/27/methoxetamine-dip...
And here's one I wrote after about 8 months of sobriety: https://thelistservearchive.com/2017/10/16/oblivion/