How to get a job interview?

I'm 16 and I've never had a job before. I applied to several places like a week and a half ago but havn't heard anything back. So I called them all back and most of them said they're not hiring till the fall/the manager wasn't in. One place I called though was Blockbuster and they said that the manager was reviewing applications at the moment. So they asked to write down my name and number and I gave it to them and the lady I spoke to said she'd give it to the manager but it's been like about 5 days now and I havn't heard anything back. Should I call again? I don't know what to do. I feel like I'm always just bugging them when I call. Thanks