A lot of people get headaches, in fact headaches are one of the most common conditions that affect us globally.
There are many different types of headaches. One of the well known headaches is called the 'cervicogenic'(cervico-: neck, -genic: originate) headache. It's a well known condition that is to do with the sub-occipital muscles.
When muscles get tight, they may refer pain to other areas. This is called the 'referral pattern' of a muscle. What I noticed as a chiropractor is patients who have this cannot pin point where the pain is, they know whereabouts, but not specifically because the pain keeps changing its location in a certain area.
Patterns I saw in my practice:
Sub-occipital muscles: back of head(most common), top of head, eye brows.
Sternocleidomastoid: Side of eye, temporals, inside ear canal.
Upper trapezius: Back of head, eye brows
Masseter(jaw muscle): Back of the eye, below the eye, side of the eye, back of head.
Pain at the back of the head is a relatively well known and easy condition to treat for many practitioners. Masseter referred pain commonly occurs after clenching the jaw while asleep, and waking up with a tight muscle. The reason for clenching the jaw can vary into neurological or psychological issues.
Masseter has many trigger points and its one of the most strongest muscles in our body. So we need to put a lot of pressure when we release it, and that can be painful for the patient as well.