Last night I woke up with a mass behind my jawbone joint and directly below my left ear on the side of my neck. The lump was hard, size of a golf all, solid, non-moveable, painful but it was not hot to touch. It is almost 12 hours later and there is slight tenderness in the same area and swelling is just about gone. I have TMJ, though it hasn t flared up in years but have noticed some tenderness in my jaw on the opposite side and my bite. Had contributed it to grinding teeth when I sleep and figured it was nothing more than that until 3:30am last night when I woke up with the painful protruding bulge on the left side. Your thoughts? I did do the heating pad since about 5am this morning until about an hour ago.