Did you agree with the original assessment that you were post-menopausal? It seems pretty early. Maybe something has been going on like hyperplasia. I believe that is dealt with by a D&C (which if they suggest it, don't worry, they're done under anasthesia.)
I would also be ready to ask for (or demand, if you can) an MRI of the uterus. It will show what's going on if it isn't just ordinary menopause.
When will they see you next? Do you have a good doctor? If so, call and say you're really frightened and distressed, and ask to be seen sooner, and see if you can get an MRI.