You're lucky you didn't end up with an ulcer. I have a friend from highschool who accidentally swallowed a quarter during a college party playing quarters. At the time everyone thought it was funny. The only problem is it lodged in her esophogas. She thought eating something "bready" like a roll would help dislodge it the next day, and she was scared to tell her parents. She ended up having to go to the emergency room and had to have it removed. Eating something almost caused her to hemorage, and partially blocked her airway. She's had problems eating ever since because of the damage to her esophogeal passage. Consider yourself lucky.
Oh, and if you do turn it into a necklace good luck explaining to women why you keep a tarnished quarter around your neck.
