When the new bridge plaza was built at the end of I-94 in Port Huron (connecting to Sarnia) the new traffic flow (compared to the one that had been there for decades) was confusing to lots and lots of people. The first several weeks there were attendants in place to guide accidental people back into Port Huron, and then changes to signage and such were made as a result of the feedback that it’s not such a problem anymore.
This very thing happened to me at the Detroit/Windsor border a few years ago. It was late, I was lost around Detroit, trying to find a bar I had never been to before, and before I realized it, I was on a one-way path to a border-security checkpoint! I had no clue how I ended up where I did, I was distracted trying to make sense of these directions I had. I had no choice but to just drive up to the booth and 'fess up.
I felt like a fucking idiot. And it didn’t help matters that the border agent talking to me was so incredulous of my story when I first told him that he was questioning me as if I were a possible criminal of some sort. I had to repeat my story 3 or 4 times before his demeanor noticeably changed. I felt like a fucking idiot.