Use it to describe experiences or situations that cause discomfort or distress, like a real bad dream would.

Negative Emotion

Best used for situations that are deeply upsetting rather than just mildly unpleasant.

Intensity Matters

It's a figurative expression and doesn't mean the speaker actually had a bad dream about the situation.

Conveys that a scenario feels strange or unbelievable, akin to dreamlike experiences.

Highlights the speaker's confusion or disorientation about an event, just like in an actual dream.

Indicates that something is being compared to the unsettling nature of a bad dream, not that it is one.