What just happened to America's Got Talent on NBC?

I was sitting here watching America's Got Talent on NBC and it was a new episode, then it said: "We now return to America's Got Talent." When it was already on! NOW there is a repeat episode running! When a new episode was already playing! They interrupted the new episode with an old one! How could NBC make such a huge mistake? Not to mention my DVR didn't tape the last episode at 9 PM even though it was a new episode, but that's an entirely different problem, but I think it may be NBC's fault also, now that this happened. Has this happened to anyone else, or is it my cable company? It seems like NBC's fault, though.