coming or going, not know if one is
Be in a state of mental confusion, as in He has so much to do that he doesn't know if he's coming or going. This idiom was first recorded in 1924.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.