Thank you, Marvin. It was, as the name suggests, a challenge. My first draft was over 150 words so I had to be brutal when it came to trimming it down.
Then you're in good shape to start working on the 300, although I don't see any likely way that anything written for this 75's theme would fit this month's 300 picture, so I'd suggest starting fresh. Aim for 150, and you should come out close to 300! Do, as TJ suggests, read the rules and be sure to count very carefully by hand, at least twice. It's no fun (I'm told) to get kicked out for being over on the word count. Pay special attention to hyphenated constructions, as they aren't automatically considered single words.