I've never had a bad trip in over 10yrs of psych use. As long as I willingly ingest it, I cannot imagine having a bad trip. Just try to relax and go where the experience takes you. In the back of your mind you know it will wear off, and it's pretty easy to tell yourself this. Also, this is why you took this drug, no? Maybe psychs aren't for you, anymore. If I find myself in a negative thought loop, I simply walk somewhere else, where there is visual stimuli (even just looking out a window), and I usually forget about it fast. Even on really high doses of acid, I've never thought I was dead or in hell, I just can't get into it "that deep", but everyone is different. My friend once flipped shit, ran his truck off the road/highway, and believed the approaching headlights were, "the light" at the end of the tunnel. But in all fairness, this was his first time using acid, and he took 3 or 4 strong hits, at a very rough time in his life (his g/f took his son and moved out).
You might want to lower your dose if you don't feel comfortable. Or keep some benzo's on hand for rough experiences. But just tell yourself, it will wear off, nothing lasts forever. Or stick to psychs like short acting tryptamines.