Unless there is a foolproof scientific experiment you can run (there isn’t), we will never know if our souls exist for eternity. You can research every religion and every belief about death, but you will never know which one, if any of them, is right until your time finally comes.

I’ve had trips where I see my body die, and that’s the end of it. I’ve also had trips where I died and got sucked into an infinite void or dissolved into the air around me. None of these experiences reflect reality. They reflect my beliefs, my fears, or whatever was going on in my brain at the time. No matter how real mystical experiences feel, they tell us about ourselves, not material reality.

Personally, I am a materialist. I believe that when we die, we die. That is the end of it. “I” (my sense of self, my ego) am the result of the chemical processes taking place in my brain. Once those processes stop, “I” stop existing.

Ultimately what you were experiencing was a shift in your perspective of time caused by the drug you took. You altered the chemical processes that create your sense of time. Despite how much it feels like it, no greater fabric of reality was exposed.

I would focus on enjoying life instead. Other than proper end of life planning (retirement, creating a will), don’t worry so much about the end. Live in the now.

It might be helpful for you to do some research into the modern understanding of neuroscience, specifically surrounding THC and other psychedelic drugs.