The left lock buggered it up? I’m guessing that’s where you go into the “garage”?
Remember, the back axle of the unit are your steering wheels. I find it helps to watch those. Just think, when you pass, you can get out and look as much as you please.
I passed class one first time and have been driving them for years, but if it helps, we all have off days. I fluffed an assessment drive at maritime a few weeks back. Had a little drive round the yard in a unit, then he told me to couple up. I reversed in front of the trailer, got out and checked the ride height, got back in and started reversing under, when he told me to stop and that the assessment drive was over. What had I done? Years of bad habits and I forget to check the trailer brake. Gutted! I wanted that job! But who cares? When you’ve passed, you’ve passed. Taught me a lesson! I won’t do that again!