Simply ask about what the status of your application is, and what is going on in the hiring process.

You will either get a straight answer which, even if negative, tells you exactly what is going on or you will get an evasive answer or a flat-out lie. You will have to assess what is going on.

It is entirely plausible that although you have the credentials for this job, that the hiring department wants to solicit resumes from outsiders simply to see who is available.
In this economy there are more job-seekers than we have been used to over the last six or eight years.

Does the hiring policy at your place of employment state that any current employee who applies for a job and who can meet the requirements of the job will automatically be placed in that job?
SRM

There are seven days to apply, but once the applications are received they are not necessarily reviewed instantly. You could call them and ask what the timetable is for the position (when will they select finalists for interviews, will you be notified either way if you are a finalist).

Just keep it free of any resentment about how long it is taking, and make it an inquiry into the process itself, and you should get a reasonable answer.