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.
Mastoiditis is a serious ear infection in the mastoid, the bony protrusion behind the ear. It often arises from an untreated minor ear infection. You may feel a knot or painful lump behind ear, due to the development of a pus-filled cyst.