Intermit daily head pain on top-back right side. Dull. CT head w/w/o contrast- Norm. Scalp seems sore in the area when pressed. No other sympts?

Possibly MFPD. If you clench your teeth or even grind(brux) at night when sleeping, the entire side of your head can ache/throb. There are muscles under the scalp that can hurt when pressed like you describe when they are inflamed from this(Temporalis). Dentists are generally good at identifying this(MFPD=myofacial pain dysfunction). It's not a dangerous condition, but depressing and painful.