Sometimes headaches can be relieved by neck traction. Here is a video showing how to do this on someone you care about. Remember to go slow and get feedback.
Here are two muscles that are common with headaches, the temporalis and the superior oblique. This video shows how to massage these muscles to reduce tension and headache pain.
This is how we test the neck when looking for a cause of headache pain. The upper portion of the neck, or the upper cervical spine, is a common source of headache pain. Testing the atlas and axis and how it moves not only gives us information on movement and pain but also a guide for treatment success.
This video is about the process in picking the right pillow for you. For side sleeping remember to 'fill the holes' and keep the spine straight with enough support. If you have tried 2 or 3 pillows and your neck pain or headache pain continues then the problem is not your pillow but your neck.
Is there an alternative to neck manipulation? This video looks into the different treatment options to restore normal neck mobility and resolve pain.