I only write flash and short story. Most of the stories I like have some kind of twist. The twist is usually something unexpected that happens or is revealed. Some time ago I got carried away and suggested a twist on a small story here. Thinking about it later I found it was a bad idea. What I had thought of as a twist would actually having the narrator deceive the reader.Maybe not lying but definitely omitting to tell the whole story. The twist is then that the reader thinks something happened but the “real” thing is something else. So actually there is no twist in the story, the twist is how the story is told. When I realized this distinction (I am still new at this) i felt: No this is not the way to do it. Now I am trying to write something for this month’s flash contest and I just found a good twist that just builds on this devious narrator. As usual, if it’s well done everything goes. But, is this the way to go?
I think it would be okay if the twist is meant to have an untrustworthy narrator, because of course they'll lie about things. I think this would do well if it's clear at some point in the story that there is a reason to not trust the narrator, because then your audience will be watching out for what's real and what's not. How does the audience find out that the narrator is unreliable? How is the twist revealed if the narrator is the one dispensing facts, as they have the ability to omit certain things and can easily leave out the clues that lead the reader to realize that he's unreliable? As long as these questions can be answered, I think your twist is fine. Good luck with it!
I'm a short story writer, too. Love the form. And love an unreliable narrator. You should be able to find some pretty good examples if you do a google search. I think an unreliable narrator is more appealing than a some sort of twist. If you are always aiming for a surprise ending all the time, it could be distracting you from what your story should or could be. And a twist can seem like a gimmick. I read a lot of short fiction and it's more rare to have the sort of twist I think you're talking about. I love unexpected turns in a story, but I don't want some sort of punchline at the end. However, I always love an unreliable narrator so I think all those twists you were writing might have led you to a good thing. I would focus more on the unreliable narrator and the story. Maybe leave the twisting out. I bet you can write a great story without it. Good luck with the contest.