Away from one's objective, train of thought, or a sequence of events, It is often put as get or put or throw off the track, as in Your question has gotten me off the track, or The interruption threw Mom off the track and she forgot what she'd already put into the stew. This term comes from railroading, where it means “derailed.” Its figurative use was first recorded in 1875.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
How to use off the track in a sentence
He left the village the next day at noon by the toy train, "the little get off-the-track," as we call it.A Village of Vagabonds | F. Berkeley Smith