If you observe your emotional responses to various situations, you’ll see (well, feel, actually) that no feeling ever appears in your head, neck, arms, shoulders, legs, or hips. We all experience emotions in our torsos. At the same time, some emotions cause secondary sensations.
For example, when we feel worried, our hands and voices can tremble; when we feel angry, our faces can turn red, and we can develop headaches, later on; or when we experience stress, we can feel tension in our upper backs and stiffness in our necks.
While stress is not a primary emotion but a reaction to an emotional irritant, it produces real somatic sensations of discomfort. It may take more questions and observations, but it’s highly likely that that my friend’s sensation in his head is a result of stress and/or suppressed anger.