Awww!! this is so painful. I can understand. I am also suffering from the same problem.
Where behind the ear? If you mean in the ear lobe, then I can say that may be an internal pimple (that's what I'll call it). I frequently have small ones about the size of a BB (think BB Gun), then every few years I'll get one much larger, say three of four times the size of a pea. When this happens it can hurt. They have always gone away, absorbed, I guess, or broken through - what a mess.
Sorry if this doesn't help I am trying to change the subject,. Perhaps you can provide more details on the location of the pain.
no its more on my head located directly behind my ear