bad trip for me was like a period of time during the trip where i experienced extreme paranoia, mostly delusional, it passed though and the trip ended up being rather pleasant
positive, im pretty sure an SUV physically flipping isnt a hallucination. the SUV flipped from one side to the other then back to the tires (this popped all 4 of his tires). me and my girlfriend were both in the backseat without seat belts and slid from one window of the car to the other. i wouldn't lie about this it was one of the scariest moments of my life and it was almost like my life flashed before me when it was happening. im just thankful that im not dead.
I saw a dragon flying around the dark parts of my room warping faces and assigning the face of people I know to it's emotions, bad would be someone who hurt me good would be someone great and what not. It was changing so fast because I was fighting against it or something. It's crazy shit. Don't fear hallucinogenics though, just respect them.