Tyler,

As Jo*Mar said, limit your risk of head impacts. If you can kick a ball without a need to head it or a risk of others kicking it at your head, you should be fine.

The neck injury is not usually a spinal cord injury. It is a spinal joint/ligament injury that can radiate when aggravated. The inflammation in the neck can impact nerve signaling that can cause a myriad of symptoms. It can change blood flow to the brain stem and such.

Icing the neck if you have a headache or any other symptoms is good. Headaches can be triggered by neck trauma, especially when you have tenderness at the bony spot behind your ears. That indicates ligament strain and muscle spasm from the neck.

An important issue for you is sleep posture. At 6'5", a bed that allows straight head and neck position can be a challenge. Your neck can be stressed when you sleep since no muscles are holding the neck in alignment.

I doubt you've had 15 or 20 concussions. More like 5 or 10 concussions and hundreds of subconcussive impacts if you did a lot of heading.

I would like to see contested headers outlawed, especially from corner kicks or in the goal box/area, maybe even the penalty area. Too many lives are changed by concussions in the goal box/area.

It sounds like you got an abbreviated sideline SCAT test. To make matters worse, nobody ever scared you and impressed in you the importance of being forthcoming when you have symptoms. They don't like to risk losing a key player. But, you can be gambling your future.