Editing your own work is always a challenge. It’s easy to read over typos because your brain tends to see what it expects. You also have your own writing style, which of course will seem natural to you, even if it has something fundamentally unclear that a reader will trip over.
One way to help overcome these obstacles is to read your story aloud. You can tell more easily if the flow of the words is natural, often discovering a better way to arrange them. If nothing else, read the dialog out loud, which helps determine whether or not it sounds authentic.