Embarrassing moments

What have you done that still makes you cringe?

When I was 18 I was instructed by the family to visit my Great Aunt because she was in a hospital which I lived close to. There was a bus strike taking place and no one else could get to see her. The problem was that I'd only seen Auntie Lilian a few times in my life but I was assured that I couldn't miss her because she looked like my grandma and was in the third bed on the right. So come visiting time I dutifully entered the ward and saw a lady who looked like my grandma in the third bed on the right. I pulled up a chair and started chatting to her. After about 20 mins she said, "It's lovely of you to visit me dear but who are you?" I started to explain who my mam was etc. only to find out that she didn't know who I was talking about. It turned out that my Great Aunt had been discharged that afternoon and no one had thought to tell me.