I was ten. Mom noticed before I did, so I didn't have any fear reaction. At that age, if Mom said it was ok, then it was. My symptoms were mild, and also ok by Mom. She tried to explain but I was bored and wanted to go out to play. She asked if I understood - I hadn't been listening but I didn't want her to start all over again, so I said Yes. The *big* shock was when it happened again, the next month. Whaddya mean, every month??? Whaddya mean, until I'm 50???