We had a similar experience many years ago, my friend got one joint from his stepsister and we had a bad reaction at a concert. I had teeth grinding and horrible visions of biting human flesh. When we left the theater I saw scaffolding on a building and next I knew was way up there scared as shit. Dont know how they got me down, either. We were mad as hell, called Deb on the carpet and she admitted PCP. One day Deb died of some OD.