What is she thinking?!

Did Nicole really think she was just going to waltz into Sami's apartment and see and/or take Sydney?  Is she really THAT crazy?!!  SOOOO glad to see Brady got a hold of her.  Can't wait to see him rip her a new one on tomorrow's show!!   And, what the heck is up with EJ?  He says to Stephano that he knows Sami kept his child from him, because of Stephano's actions, yet the preview for tomorrow shows him threatening Sami again.  I don't get it!