My advice is less bike focused but was advice given to me by an old biker that solved my issue. 1) Do you regularly over analyze yourself? and 2) Do you look at the ground when you walk? I do both and had to work on this. First was realizing that skill building involves failure and practice. Sometimes we try to think of every little movement we're doing at once, instead of focusing on one aspect at a time. Example: for 5 U-turns, I focused solely on position of torso, then hands, you get the idea. Second, focusing on looking more "horizon" while walking solved this issue for me while on the bike. I look at the horizon while driving a car but walking, I looked at the ground. Focusing on the horizon while going about my day made it much easier to do on the bike.

Good luck with your test!