my experience was similar. my parents (or mother, really, to be more fair) tried very hard to prepare me. she also found my undies, and i also suffered no more trama than, "oh, there it is." i remember just sticking a pad on my undies like an old pro and forgetting about it.

the coolest thing was i got it on new years eve when i was in 6th grade. i thought i was special. :D