I did a few moths ago. Yesterday, I did it for like my fourth time( it was at a party) and it wa sa huge joint, like 3 cm in diameter. I took a few hits and went inside. Like 5 minutes later , I noticd my heart beating fast, like insanely fast. Maybe like 220-240 BPM. Anyways, so I was scared about this, then I started to twitch, first with my legs then my arms. I tryed to go on a coputer but I couldn't decided what site to go on so I went and laid down in a spare room. While i was on the bed, I began to twitch so much, like i was shivering. All I could think about is how I wanted to to stop. So many thoughts were racing through my head, and all this time my heart beat was insane. I tryed to go to sleep but my friends came in and jump on me, but once they left, I thik i fell asleep for 5 minutes but I woke up and was ok. I went down stairs and watched amovie for 30 minutes and then I was fine. I have decied after that night that I will never ever smoke marijuana ever again. And being sober at a party is just as good. I am not being a weed hater or anything, it is jsut my opionin.