bad trip - Phrases/Idioms
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
A frightening or otherwise very unpleasant experience, as in Given the poor turnout, her book tour was a bad trip. The term comes from drug slang of the mid-1900s, where it meant experiencing hallucinations, pain, or other terrible effects from taking a drug, especially LSD. It was then extended to any extremely unpleasant experience.