Yes, that's certainly embarrassing. Glad you got to the bottom of your problem!
Mine weren't my shoes (flip flops), I'd been walking for days in those flip flops in 2015, wore them during the summer of 2016, killed them for 8 Disney days in November 2017. I have never had foot fatigue. I know where my fatigue came from. It was from the fact that I was about on day three of the CONSTANT walking in the flip flops. My body was just getting used to it. By the next morning I was back out on the WDW trek and no more foot fatigue problems. I am also more fit than I was in 2015. So during my 2017 visit, I wondered if fatigue would set in, but not once. And I did 17 hour days for 8 days straight. Really proud of that 2017 trip!
Your fall reminds me a a pro soccer player friend (in the 80's) who was wearing cleated footwear. He went to slide into a kick, but on whatever surface he was on (I forget the details) the cleats did not ALLOW him to slide, so his leg was stopped, and his knee went pop. Career stifler.