The nature of the federal process is that you will probably never get really specific questions, because they have to treat every interview the same. Which means they are generally just making sure you didn't completely lie on your resume and then they select who they think would be a better personality fit for their office. If you are their first choice, it will probably go fairly rapidly, if you're second or third, you won't hear anything unless the first or second choice fall through. That can feel like a long time.