@Guantanamera
I'm not sure if excessive piercings would help in passing, but I imagine it would be a function of how the piercing was done. As far as finding cute earrings, look around at the jewelery counters of your favourite department stores. Also, Claire's, which was mentioned above, has a large selection of cute and feminine earrings for girls and young ladies. Some of the styles are a little too young for the older ladies in the crowd, IMO. Good luck!