It's broken! I can't report my own post as spam?
I'm thinking that you are kidding... but just in case you aren't, that is correct... the report spam button is not shown next to your own posts and it is not shown at all if you are an admin.
In both cases it didn't seem necessary, but it also looked cruddy as well. In both of those cases you'd also see an 'edit' button, and the extra button was causing the whole button bar to wrap