How many times should you call an employer before putting in an application?

I'm 15 and I applied to a job about a month ago and just last Friday (the 18th) I called and talked to the manager and I asked her if she got my application and she said yes and that they might be hiring within the next 1-2 weeks so she would call me. Well it's almost been 2 weeks but my aunt said I should call again and just keep calling until I get the job. I'm kind of nervous to call again though because I don't want to seem annoying and I wouldn't know what to say. I really need the job though so I was just wondering what you think I should do. And if you think I should call, what should I say?