With that kind of pain, you'd be grouchy too.  See if you can't give Taz a
bit of warm water.

From http://www.everything2.com, this is what an abscess is:

A section of an organ that has been broken down, surrounded by an area of
inflammation and infection. It takes the form of a rounded capsule, and
walls itself off, keeping the rest of the body from sepsis, but slowly
getting the infected area worse. They are usually filled with pus.

You can have an abscess in any organ, including extremeties. Most common
cases are the lungs, I don't know how rare brain abscesses are.

Lung abscesses are usually caused by the inhalation of a foreign body like
a peanut or tooth that jams itself into the lung tissue and inflames it.
This happens in deeply unconscious patients or people who lack a gag
reflex. It can also be caused by Tuberculosis as the body tries to contain
the infection, or other airborne septic material.

Sometimes surgery is needed to remove it, sometimes just antibiotics and
drainage (see postural drainage). In lung cases, a bronchoscope can be
used to remove whatever object exists, unless the abscess is closer to the
outside of the lung.