Tl;DR Almost died. Don't do it!
Might as well share my story with synthetic cannabis.
As a teenager living in country where weed is illegal and in some places might be hard too come by, it was nice finding out that i could order synthetic cannabis online, and have it delivered by mail without any problems.
My first attempt at smoking this was with something called Yucatan Fire. It was a nice smoke, and didn't have any problems while smoke this.
After finishing smoke that, i bought a bag of a "BlaBla".
I took the same dose as usual which was around 0.5g i think, and smoked a joint with this stuff.
After coming out of the shower it suddenly hit me. Everything was were vivid, and my mind was drifting off.
I then made the mistake of taking a nap thinking that i could just sleep this off, but oh no.
My mind went into a kind of lucid dreaming. Everything around me disappeared, i was trapped inside nothing. In my mind there was not anyone else left in the entire universe but myself.
At this point i wake up, and i'm just freaking the hell out. I have never been that scared in my life before. For some reason the only solutions i can think off, is that for this too stop i would have to kill myself.
I decide to go down to the kitchen, but half way down the stairs i hear my mom come home. I rush back to my room, and after a little thinking decided that i should go down and ask for help.
I tell her that i have fucked up, and smoked some things that i properly should not have done. I keep calm and tell her that i really need to go to the emergency room.
While she was getting ready to go, the only thing i remember before being at the ER laying in a bed, is just sitting in the couch and crying. I can't even remember why, but it was diffidently the worst experience off my life.
I was told by the doctor that i might have died if i didn't come, so i consider myself pretty lucky.
Haven't touched the stuff since, and will never do it again.