Please Advise Me, Oh Smarty-Pantsers Out There

     Here's a question for all those smarter and/or more experienced writers than me, or for those who have just gone through this particular problem before.
     I sent a query to a specific agent, followed all the guidelines, and never got a response. On their website it says that if you don't hear from them after eight weeks, you can resend. So I did. Again- after eight weeks- no response.
     What do I do? Do I send it for a third time? That seems almost pushy to me. Or, do I try a different agent within the agency? Or is that bad form. I don't know what to do and I don't want to be a pest.
     Any advice?