.....I must admit to looking up this phrase/wording as never seen it before,.and after reading several interpretations on Internet, thought the following sums it up, at least for me. Hope you don't mind my adding .....
although "crash and burn" seems a bit strong interpretation, it does seem close to some of my personal experiences, a bit more so than "the well laid plans of mice and men"?

Internet:
Gang aft aglay
The quote comes from the poem, "To a Mouse", by Robert Burns. He has been lionised as 'Scotlands National Poet', so I would assume that the language is Scottish. As to the meaning, you are indeed correct. It does mean to go astray, but I would suggest that to go astray would be a rather weak translation. Perhaps to crash and burn is closer to the spirit of the poem