Like blacbird said, a lot of short fiction is situational. You don't need to show some huge personal growth or development of a character. Think of it this way: your characters are already developed. They are fully rounded human beings. All you have to do is pick which bits of them you want to reveal to your readers.
I can (and frequently do) tell a story in a hundred words or less, and very creative writers can do it in three sentences, or the space of a Tweet. Yes, it's hard, but you have to read and read and read. Study how others do it. How they make so much happen with so few words. And you have to...
...completely abandon everything you know about the beginning-middle-end story structure. Even though most fiction, even short fiction, will have a beginning, middle and end, sometimes it can be harder to see in short fiction because you don't always have the same conflict-reaction-resolution themes to play around with over a longer period of time. Sometimes the story is a snapshot of the character's life, and the underlying themes/lessons are implied rather than explicitly stated.
You may be struggling with how you are defining "ending." Short fiction does not necessarily have a wrapped-up ending like longer fiction.
This evening, I went to the supermarket to buy a bottle of whisky, but they'd completely sold out. Miffed about my impending sobriety, I dodged the checkout queue and caught the early bus home. Five minutes after I got on the bus, a drunk-driver ploughed his Golf into the bus shelter. Had I still been there, I would've been killed instantly. I could still do with a stiff drink, but I'm not quite so disappointed about how my evening turned out.
How short are we talking? I can point you to some great sources for drabbles (100 words) or flash fiction (up to 2000 words). If you're looking for something a little longer, there are plenty of short story anthologies out there covering a wide range of different genres and subjects. The more you read, the better your understanding will become, and this will help you to write.