I once chased a doctor down the hall when he did that to me with an appt for my daughter. He was an assembly line doctor, we were living in a rural and rather backwards community at the time, and he was accustomed to running in and out and not getting any questions from patients or parents. He was God, in his own eyes and the eyes of his patients. He spent all of 2 minutes with us, made his proclamation, and out he went. I shot out of that room faster than even I knew I could move. I was livid! How dare ANY doctor treat ANY patient or family member like that! I yelled out, "wait, I have questions!" He turned around and, clearly annoyed, asked me what I wanted to know and answered my questions. Funny, though, as I asked my questions and reacted to his answers, he softened up, as if he recognized that for once he had someone with half a brain in front of him who really wanted to know what was up, wasn't going to go away without answers, and who understood what he was saying.
Yes, find a new doctor, but in the meantime, get his nurse on the phone and politely demand more information.
Just my two cents worth...