Half of my building is occupied by the Coast Guard. Since the shutdown, non-essential employees have not been coming in, so the parking deck has been a delight. Parking 2 floors down from my normal spot every 3 days in a row now.
Does it make a pop or does it feel like there is a knot being pulled through a hole that is a little too small? I've had the same sensation after a few long runs and came to the conclusion it was from a breakdown in form as I tired. I felt it most after sitting for awhile then walking up or down stairs. It went away for me and I was back out after a few days, but I'm interested to hear what you find out.