OK, so, my first mistake was not the decision to go back to my Air BnB and rest up before the GRL evening program. That was an entirely logical and sound decision involving wise and judicious boundary-setting.

No, my first mistake was, having gone home, deciding that to relax I would eat – alone – a single-serve pot cookie, recommended by the dispensary as a gentle option for newbies who haven’t touched marijuana since 1991.

My second mistake was thinking, only an hour later, the cookie wasn’t working.

My third mistake was eating the single-serve THC chocolate.

My fourth mistake, and this, I think, was the critical one, was the brainstorm that – having ingested multiple THC-laden products – what would really relax me was a two-mile walk around a strange city. Again, alone.

The gravity of my compounding errors appeared one mile out when the time dilation set in. I’m not sure if the paranoia or the deja vu came next: both came before sensory distortions.

It took either five minutes, or around eight Martian years, to go from walking on a pavement beside a busy road, to traversing a black-sand beach atop ragged white cliffs, at the bottom of which ran a buzzing ribbon of expressway traffic. By the time I was 0.8 miles from home the small part of my brain that was not currently walking in an alternative reality – yellow, in the key of peppermint, and flavored with disquiet – remembered there’s a bloody good reason why I didn’t smoke pot for the last 26 years. Being utterly unable to restrain my mind from wandering really freaks me the fuck out.

Having floated home I curled up helplessly on the bed as my synapses buggered off to the playground beyond objective reality.

For five hours.

It was not fun.

The takeaway: when in Denver, imbibe with friends, single-serve means single serve, park yourself somewhere safe, and skip the aerobic exercise.

Oh, and I have two pot cookies available.