Oh, exciting. I've never thought about a writing contest before. Has anyone entered any contests before?
I spent most of 2016 entering writing competitions. One problem I immediately found, was that 99.9% of contests only accept work that hasn't been previously published anywhere, including as an eBook. As I'd uploaded most of my poetry, short stories and novellas to Smashwords and Amazon in 2013-2014, I had to write fresh material to enter competitions.
Many stipulate a theme that they want the story to be about, and I reckon that most organisations running the competitions take a very literal view of that theme. For example, I entered one short story competition with the theme of Exit Earth. I'd written a horror story featuring a soil demon, the amalgamated souls of slaughtered English Civil War soldiers, which had been snatching people from fields for 400 years—literally exit earth! The competition winner and all of the shortlisted entries were about ecology, with some describing off-Earth colonies due to the planet being ruined.
It really pays to investigate who is judging a competition, and also look at previous winners—how they interpreted the theme, what's happened to them since they won, such as did they lever a publishing contract out of winning and have they had a successful career since? I came across several writers who'd won more than one competition, but had never published a book, not even online. Some writers appear to specialise in entering competitions, their names appearing time and time again on longlists. Judges are usually published authors, so see what sort of stuff they write, what their views are from their social media posting.
Also, if you're thinking of entering a foreign competition, check who's won before. There are many more competitions based in America, some claiming to be international in scope, but after entering a couple of them, I looked at the winners—and there wasn't one who wasn't an American citizen.
Lastly, don't wait on tenterhooks for the result. Like submitting to literary agents, get on with more writing and forget about your submission.