ppl are speculating Tyler finds the drawing and then goes to Klaus to confront him and when Klaus sees that Caroline kept the drawing goes after her again. Obviously he'll be too busy to think about how to get Caroline to worry about Tyler.
Also, ppl that were around when they were filming 3x20 saw Klaus go to Elena's house and knock on the door. She slams the door in his face, but then he breaks a window apparently with a piece of paper. Don't know if this is true, but there was something about breaking windows and Klaus having paper/a note in his hand anyway. And I did saw some 3x20 BTS pics of JoMo with fans somewhere near a house that looks like Elena's. Some are saying all the girls are inside the house getting ready for the dance and Klaus goes there to talk to Caroline, but Elena won't let him, so he makes a scene. I don't know what to think anymore. I will go crazy waiting for this ep.