There is a bump behind my ear lobe (where it

Patient: There is a bump behind my ear lobe (where it joins my skull) that has been around for a few months. At first I thought it was a pimple, but it wouldnt pop. It felt like there was a build up of fluid inside, and it was putting pressure behind my ear, so I sterilized a sewing needle with a little bit of rubbing alcohol and punctured it. Its been 3-4 days since then and its been continuing to leak a clear oily fluid, and occasionally a very small amount of blood. What is it and what if anything should I do?

Symptoms: Pressure, leaking clear fluid.

Doctor: