Lucky you! Looks like a tiny, perfect quahog pearl! If it was cooked, it may not be durable.
One that size is not worth a whole lot, not as much as the story you can tell for many years then produce that little fellow! Don't try to have it drilled. They shatter. If you want a little pendant or something, put it in a claw setting. Otherwise get a tiny plastic gem box with a plastic lid and display it.
Though tiny, that is one perfect pearl!