Anxiety Dreams

A character has a dream, literal or symbolic, about something he dreads will come true.

Not prophetically—this trope is to Dreaming of Things to Come what Bad Dreams is of Dreaming of Times Gone By. Though confusion is possible.

Unlike Bad Dreams, this can and usually is overcome by doing the dreaded thing, or getting past it. Except where they are one and the same, fueled by a fear of facing My Greatest Failure again—in which case facing it will still fix the dreams.

Super-Trope of "Not Wearing Pants" Dream.

Truth in Television. In fact, some posit that this is the reason we dream—you run through the worst-case scenario in your mind so that if you do end up running from a herd of rabid t-rexes with laser vision, you have more of an idea for how to handle it.

Literature

 * In Harry Potter and the Prisoner of Azkaban, Sirius's anxiety dreams are revealed his Talking in Your Sleep -- "He's at Hogwarts"—although explicably so only with the knowledge that he just learned was at Hogwarts, ready to strike.
 * In Eleanor Cameron's The Court of the Stone Children, Nina dreams of trying to look up her phone number in the book although they have just moved there and wouldn't be in it. (She's already gotten lost once.)
 * In Adrian Tchaikovsky's Dragonfly Falling, the Emperor has dreams about his sister, his only living relative and so the only other person who could claim the throne.
 * In L. M. Montgomery's The Blue Castle, Valancy dreams that she is confronting someone whom she told something that proved to be false, and he proves to be made of glass and breaks.
 * In Devon Monk's Dead Iron, LeFel does not sleep because he will only dream of dying, which is near.
 * In Devon Monk's Allie Beckstrom book Magic to the Bone, Allie comments on how she does not have them, sleeping on the drive to a friend's, escaping a city where she's suspected of murdering her father.
 * In Jack Campbell's The Lost Fleet novel Invicible, Geary's Bad Dreams are mixed with this; he tells Desjani that he dreamed of her death. She tells him that His Heart Will Go On will be his duty.

Live Action Television

 * One late episode of Frasier is dedicated to the main characters' anxiety dreams — Frasier dreams that Roz is berating him because his radio booth is full of cobwebs and no one has called in six months, reflecting his worries that his show might be declining as well as his fear of being alone, Niles dreams about accidentally baking his unborn baby into a pie, reflecting his fear that he's going to be a bad father, and Daphne dreams about inflating comically while Niles cheats on her with several supermodels, reflecting her fear that motherhood and age will affect her marriage. Martin, on the other hand, just dreams about singing and dancing with his new girlfriend in the style of Fred Astaire and Ginger Rogers — without his cane.
 * In the first series of Buffy the Vampire Slayer, everyone's dreams start to come true. Most are "classic" anxiety dreams such as being in class in one's underpants (Xander), having to sing in public (Willow), losing the ability to read (Giles), and having to sit a test for which she had not taken the class or studied (Buffy).
 * In "Restless" Willow dreams that she's turned up for a play without having learnt the lines, then she has to deliver a talk in her Season One nerd persona before a classroom full of her jeering friends. Xander's dream involves him going to the toilet, only to find the entire Initiative is watching him and taking notes.
 * A more subtle version is in "Hush" when Buffy has an Erotic Dream of kissing Love Interest Riley Finn—except it's taking place in front of an entire class, showing her nervousness about trying to get his First Kiss.

Music

 * In Flight of the Conchords, Mel has a song about wanting real life to be more like her dreams. Some of the dreams she mentions are stock anxiety dreams, like being naked in public and taking an exam you don't know any of the answers to. (Oddly, this doesn't seem to affect her desire to live in a dream world at all.)

Newspaper Comics

 * In Rose Is Rose, the greedy Clem has a nightmare where he shared all the brownies and left none for himself.
 * In Peanuts, Snoopy dreams of Charlie Brown's flying him like a kite, so that he crashes into the earth and shatters. Waking he blames the 30-inch pizza eaten just before bed.

Webcomics

 * Dork Tower: Once he had them about school, now about running games.
 * In Quentyn Quinn, Space Ranger, anticipiated dreams about an assassin.
 * In Sinfest, Pooch dreams that Percy vanished -- much to Percy's discomfiture.
 * And Li'l Evil dreams of himself as good.
 * And Squigley of his debt problems.
 * In Prickly City, the voter who cast the deciding vote to elect Kevin, Lost Bunny of the Apocalypse, to the Senate (and get him out of Prickly City), has dreams of his campaign for the presidency—combining this with Bad Dreams.
 * In Squid Row Randie has them about Christmas -- in October.
 * And about her job and Ryan's -- jumbled together
 * In Sandra and Woo, Woo dreams of being replaced.

Web Original

 * Phase of the Whateley Universe has anxiety Dreams regularly, and often wakes up in a sweat from them. They're not prophetic, just symptoms of his stress.

Western Animation

 * Happens to Aang repeatedly in the Avatar: The Last Airbender episode "Nightmares and Daydreams", about his upcoming battle against Firelord Ozai. He tried not sleeping because the nightmares were so bad, but then he went into sleep deprivations and started hallucinating.