Having a smoke once is not possible, perhaps, but smoking a few grams a day for several years, people become inadequate when they are released. I knew one person who couldn't even go to work without blowing. He was furious when he was sober, reacted inadequately and was irritated at absolutely everything. Perhaps this is a problem of the psyche of a particular person (although this is not an isolated case). In general, I think it is better not to embark on the path of such an experiment.
Yes. There is such a thing as "hash psychosis" or "cannabinoid psychosis", which can develop into dementia.
Symptoms: delirium, hallucinations, unreasonable laughter, distracted attention, impairment of short-term memory, suicidal tendencies, sleep disturbances, detachment from the environment, etc.
Most often occurs with abuse. ;)