I second this. You seem to be going reasonably well. I know I have trouble getting it all out on the page. Though I also have ADHD so that definitely adds to the inability to keep writing out my ideas. And please don't think your obligated to make a story bigger. Just to be clear. There's no best word count. If you really want to make it bigger, sure, but you might want to consider leaving it as it is. It sounds like you have potential simplicity issues though, so based off that impression I'd say you are probably right.