Basically, BC stands for before Christ and AD stands for Anno Domini, Latin for in the year of our Lord.. The transition point between BC and AD marks the approximate time when God incarnate came down to earth to live with His creation.
The only area that is involved is the spot direcly behind my right ear lobe where it sinks in, not futher behind where the gland or lymph node is. I have gotten swollen lymph nodes before, this is very different. My inner ear, and throat and all other surrounding areas aren't in pain at all.
One painless lump behind ear type is called lipoma. This is a relatively harmless deposit of fat under the skin. It can also be found on the neck, back, shoulders, arms and thighs, but normally it is a soft painless lump behind the ear that is due to the development of fatty tissue that grows slowly under the skin.