About your question, I like what Wikipedia has to say ( http://en.wikipedia.org/wiki/Short_story ):
Short stories have no set length. In terms of word count there is no official demarcation between an anecdote, a short story, and a novel. Rather, the form's parameters are given by the rhetorical and practical context in which a given story is produced and considered, so that what constitutes a short story may differ between genres, countries, eras, and commentators. Like the novel, the short story's predominant shape reflects the demands of the available markets for publication, and the evolution of the form seems closely tied to the evolution of the publishing industry and the submission guidelines of its constituent houses.
I guess the answer is that. Common sense rules what's the length of a short story. I have seen shorties with 30 pages, I also have seen with 10. Of course, most of times, such small short stories will most likely be published in a book with other short stories.
Put yourself into readers place. Do you - as reader - think it's a short story or more like a chronicle? Would you pay $0.99 for it would only $0.49. I guess the answer likes with common sense and how the customer will see your story.
Just a small edit: please check "Do I still need to follow the arbitrary word count limits" (Self publishing: Do I still need to follow the arbitrary word count limits?). Steven Drennon made a nice answer that shows, in pratice, what I mean about users reactions to book sizes.