Hmmm. I'm glad you put the complaint on hold for the time being.

Did you cancel your appointments with this T, and not have any on the books, when he called you "out of the blue?"
Did you say you were not coming back (before he called and asked you to come in?)

I understand you need therapy, however if you feel he is unethical enough for you to have filed a complaint, why go back?

If you canceled all appointments; made a statement even to his voice mail, email, or secretary that you weren't returning, then his contacting you was unethical, btw.

If you really think you overreacted, then by all means go back and discuss this with him. Give him a chance to explain, and also to gird up his boundaries so that he doesn't breach them again, in your mind/eyes. You don't have to sit the whole time if he becomes upset and beligerent etc, but can get up and leave. I would hope that it's a big misunderstanding, and that you can progress in your therapy.

However, if you go back, and don't discuss this, and don't find any issues with this therapy session, and continue with the complaint, that probably won't let you feel good about it.

TC