I've always found it helpful to talk these things out, but I'm very open about what I'm feeling. If my therapist has done or said something that upset me, I say it. It's happened a few times, and she's known right away that it was a problem even without my saying anything. We work it out right then and there, and it's done.

If your therapist is encouraging you not to dismiss your emotions, he'll see it as a good thing that you're upset with him. You can work it out.