The headache pain could be caused by some damage to your spine, but I'm wondering if you are taking pain medication for you injuries. Taking pain medication too often, too much, or for too long can set up a rebound pain situation. Prescribed or OTC pain medication can start to give you headaches everyday if you fall into a rebound cycle. The only way to get rid of the pain is to clean out your system of all the pain meds. Hanging out for several days without any pain meds is not a fun thing to do, but it's the only way to break the cycle. Once you have cleared out your system, the rule of thumb it not to take pain meds more frequently than instructed, don't take a higher dose than recommended, and don't take pain meds more than two days a week. This should keep the rebound headaches away.
As far as nerve blocks go, they can be very effective when injected into the spine. I have major back problems, and have to get a series of three epidurals every six months. Because my migraines are very resistant to any preventative medications(been through them all), I saw a pain specialist who tried a series of occipital nerve blocks in my head. The first injection was at the base of my skull (on the side I get my migraines), the second behind my ear, and the last one over my eyebrow, all on the right side of my head. Those injections are not particularly pleasant as you can feel the needle actually hitting the skull bone. Unfortunately, the nerve blocks in my head didn't help my migraines at all, although they are successful for some people.
Keep in touch and let us know how you are doing.
"The weather is here, I wish you were beautiful."