I was a conscientious student, even at age five. My card stayed green the whole year, except for one day. I was screwing around a little, off task with a friend, when my teacher turned my card over to yellow. In an instant, my world screeched to a halt, my stomach dropped out of my shoes, and my throat closed as I tried not to cry. Eventually my card turned back to green, and life went on as usual. But I never forgot that feeling.
At age twenty-five, I was on my first medical rotation, in my first operating room. I carefully scrubbed in and was watching the surgery from a ringside seat. The surgery went on for an hour, and stretched on to two, and I absentmindedly scratched my nose. (When you scrub in, you can't touch your sterile gloves to your mask or hat, which are considered "clean" but not "sterile.") One nurse caught me, and I was thrown out of that OR faster than I knew what had happened.
And suddenly, I was five again. Horrified from head to toe at the consequences of my thoughtless action. Throat closed, I waited for the surgeon from outside the sterile doors. He came out, and was actually very kind about the incident, saying that it happens to everyone, and provided more specifics on sterile procedure. But I just remember that feeling being exactly the same, twenty years later.
My dad often quotes Paul Simon, saying "After changes upon changes, we are more or less the same."