I wrote recently that sometimes the problem of not being able to end your narrative can be more a problem of not knowing how and where to begin. One suggestion I have for writing your story in a short narrative is to encapsulate your idea in a single scene. Instead of trying to include all the events that lead up to the main event and all the events that follow, try writing about one single event. You can then suggest what might happen after or what might have occurred before and leave it to your reader to ponder upon it.
- Your main character is excited/disappointed/exalted about a crucial sporting match (eg: grand final). Rather than writing the whole story of preparing for the match, playing the match, winning or losing the match and the aftermath, why not write a single scene encapsulating the character’s thoughts and feelings leading up to the match or during a single play or after the match. You can then suggest how the character and his or her team mates were feeling before or after by using brief flashbacks or premonitions. Imagine it as a scene in slow motion and capture the moment in detail, the setting, the actions of other characters, the thoughts and feelings of the main character etc. You could set the scene on the bus on the way to the match with all its nervous energy and anticipation. Or you could set your scene at the moment of the winning play.
It may seem that you need to write a lot more to tell your story but sometimes a single moment can encapsulate a very big idea.