sounds like you were triggered - is there past abuse? it could have brought back body memories/
My pdoc asked me to lie down while he talked me through a relaxation technique and i had to get up told him I was panicking that althoug I trusted him I couldnt lie down - this could be the same thing.
(if ok)
how are you going now?
__________________
Its not how many times you fall down that counts 
its how many times you get back up! 
(Thanks to fenrir for my Picture 
)
When you have come to the edge of all light that you know and are about to drop off into the darkness of the unknown,
Faith is knowing One of two things will happen: There will be something solid to stand on or you will be taught to fly.
by Patrick Overton, author and poet