I tried a whipped ganache recipe today. It was really good when I first mede it but after I chilled it and whipped it again, it got kind of chunky. Is this the way it's supposed to be or did I whip it too long?

usually you don't have to whip ganache long, it may have been too hard when you chilled it and therefore left chunks in the whipped ganache the second time you whipped it. If you let it get to room temp first it should not leave peices in there. If you can't wait all day for it to get to room temp you can heat it just a little to try and soften it.