It sounds to me like your first effort should be to take care of your neck, especially your upper neck. Trauma to C-1 to occiput can cause inflammation that disrupts blood flow and causes every kind symptom you are having. An upper cervical chiropractor may help Directory - NUCCA - National Upper Cervical Chiropractic Association
A PT who has expert experience with upper neck therapies could also help. Treatment should be very gentle to facilitate healing without causing inflammation. You should be icing in a good head and neck posture.

Either a chiro or PT or maybe osteopath can help but you need to find the right one. Most are just book learners. Others have developed skills far beyond traditional training and are far better. It takes a lot of time and effort to find the 1 in 8 or so who is really good.

Some of your sleep issues sound like mine early on when I had problems with inflammation in the upper neck and brain stem. Any odd posture caused problems.

You need proper blood flow to the brain to get quality sleep. Inflammation is your enemy. Anything you can do to reduce it will be good. Anti-inflammatory diets have helped many.

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