Sharp localised pain on left side of head above the ear ?

Tmj: You likely have tmj. A way to tell is to open and close the jaw with a finger placed in the TMJ socket which is roughly the pocket created when one opens the mouth and places a finger directly in front of the ear canal right at the level of the sideburns. Softer foods, warm compresses and Motrin should help. Avoid gum chewing. Temporal arthritis is another possibility.