Wife have pain on the right side behind her ear. tried tension headaches. i'm thinking stress, or lack of sleep. best way to treat this is how?

Time of headache: Few people wake with a muscle tension headache or get awakened by a muscle tension headache. Avoid light and loud noises, basically all stimulus. If she wakes with headaches i would be thinking more than muscle tension though they also can be very painful.

Could be TMJ/TMD: This could be a case of tmj/tmd. There are several other symptoms associated with TMJ and you should research and consider getting to a dentist or TMJ specialist.