I noticed my mom's upper jaw just behind the left ear is inflamed. she has head ache & couldn't raise left arm. no fever. can swallow normally.?

Ear inflammation: The most common causes of redness and inflammation behind the ear are: skin infection, cysts (infected or inflamed), or infected lymph notes. There is no obvious way to relate this directly to your mother's complaint of inability to raise her left arm. If she truly is unable to lift her arm, then she should see a doctor to make sure she is not having a stroke.

Primary Physician: Please have your mother visit his primary physician, to evaluate her neck & peri-auricular area there are a variety of lesions that can cause spasm of the muscles of the neck.

See md ASAP: Can't tell here, but not a good combination of symptoms. Could be infectious, inflammatory, tumor, stroke, etc. See md or er now.