I think one of the most embarrassing things that happened to me occurred when I was a freshman in high school. I was went to the school nurse to get a sports clearance checkup. When I came into the office one my fellow students was at the front desk. She helped out there answering the phone and filing stuff after school.
Her name was Sandy and I had always wanted to ask her out, but the both of us were terribly shy and I never got up the courage.
The nurse called me into the exam room and as she was closing the door she told Sandy to be sure to let her know as soon as someone dropped off a report she was waiting for.
She had me take off everything except my underwear. She went through all the usual stuff and finally announced that the last thing she needed to do was check me for hernias and that I should pull down my underwear.
I was mortified but a pulled them down just a little. She told me to put my hands behind my back and reached over and pulled them down all the way to my ankles.
Right at that moment there was a knock on the door and Sandy said through the door that the report had arrived. The nurse told her to bring it in.
I almost fainted as the door opened and Sandy walked in. I was standing there in full view as she walked in. She was looking at the floor as she walked in and apparently didn't realize I was standing there naked. She got about half way across the room when she looked up and looked right at me. She stopped dead in her tracks and her eyes opened in surprise. She turned bright red and immediately turned around.
Meanwhile the nurse had begun handling my genitals and although I wanted to turn around or pull up my underwear it wasn't possible with her finger pushing up into me checking for a hernia.
She said turn your head and cough and then she told Sandy to come over and put the report on her desk.
Sandy had to walk around behind me and when she did I tried as best I could to cover my bare butt. As she came around in front of me to leave the room I noticed she was looking down at the floor and trying not to look at me.
The nurse stopped her when she was right in front of me and while she was still messing around with my genitals she told Sandy to be sure to call and thank who ever it was that sent the report.
Sandy was still looking down at the floor, but since she was standing right in front of me I knew she was also seeing everything the nurse was doing. She told the nurse she would call right away and turned to leave, but just before she turned around she looked quickly up at me. I guess to see if I was looking at her. Our eyes met for a half second and we both blushed. She turned quickly and left the room.