Nothing as odd as that, fortunately, but have had more than my fair share!!
One that comes to mind straight away is the first day of the 13/14 marking (Saturday March 2nd I think it was). Being assessed by the man known as the most generous aasessor in our Supply league. Local derby, two high flying teams, all set up for a perfect day for assessment!
22 minutes in and I turned to sprint and BANG! I feel my tibialis anterior (the muscle along the outside of your shin) ping. Absolute agony. However, I didn't want to blow up and stop the game as one team were on the attack and looking very likely to score. I was in a reasonable position anyway so decided to wait for the ball to be cleared or go out of play. 2 minutes later the defending team finally smashed it up the field, whistle blown, game halted, replacement official found!
4 weeks later, I returned to refereeing...with the home team being one of the teams involved!
Never had pain like it!!!