Someone answer ASAP!!!! Ok today at 8/7c is there going to be a new episode a Criminal Minds called the Performer about a rockstar with fangs or something like that right?

Hi, yes that's right.
The Rockstar will be played by Gavin Rossdale.
Here a Link to a comment about the Episode.
link R4%2BWkhsyDML5ZSdFpf DB3Vd9XTck%3D&tsp=1257959835332

And a Promo of the episode.link

Hope this helped.:)

and its usually on at 9 EST. is the time changed tonight?

Yes...Yes there is...