Headache and neck pain can come from many sources. Most of the headaches I have treated are tension and migraine headaches. Many migraines are due to hormonal imbalances and for that I usually order saliva tests and hair analysis and routine health evaluation questionnaires, and blood tests if necessary.
Many headaches are the tension type and these in my experience start with neck tension that in many cases is aggravated by upper back muscle imbalances. Neck tension can also be a large factor with migraines.
Neck pain can come from past and recent whiplash injuries. It can also come from mattresses or pillows that fail to give proper support, causing you to start the day with pain that gets better as you move around. Unfortunately, as time goes on, this kind of pain can get worse.
Spending too much time on your cell phone or computer, or sitting in your recliner watching TV, can lead to neck pain and headaches. You may say, "None of this really bothers me - I'm fine." But as your spine ages, and you become less active than you should be, it is less and less able to adapt to the 'usual stresses', resulting in more discomfort.
The good news is..age is less of a factor if you take care of yourself. Now is a great time to start!