Ethical/Unethical Lawyer Behavior?

My sister and I recently had to obtain a lawyer for my 80-year-old father who was injured in a car accident for which he was not at fault. The lawyer presented himself very well at initial consultation. Now that the work has begun, we've become concerned about his performance.

I recently called on my father's behalf (from my mother and father's home - with the two of them sitting right there with me) to inquire about a letter he'd sent us and about the case and some of the things he was advising. He became very agitated when I questioned him about his advice. During the conversation he said some things that were very alarming to me. By the end of the conversation, he had spiraled out of control and I had to continuously ask him to agree to end the call because he was "out of sorts."

I told him that he was yelling and that I thought we should end the call until he was more calm (another day). He just kept yelling that he was not angry, but that I was. I finally was able to get him off the phone. The next day my father received a certified letter from the lawyer stating that I was very abusinve and beligerent with him and that he would not take any calls from me and that I could not come to his office, etc.
My parents were shocked at the letter, since they were sitting right there with me during the conversation.
Is this ethical behavior? Is he allowed to make these false claims to get out of answering my questions? What recourse do I have?