How far into your application are you? Back when I was applying, my BGO would not speak to me until the rest of my application materials were already submitted.
Also, it depends what you sent. Was this just an introduction, or did you have some action items that you need his or her assistance with. If it’s the former, I don’t think it’s necessary to reach out again in the immediate future. In the professional world often you won’t get a response to an email unless there really is a need for one, just because people are so busy. I’d give it at least another week unless you do have a time sensitive question.