I've had several concussions in my life.
I still remember many years ago when I had taken a bad fall on some ice, and my doctor saying "if you have another concussion, it may be your last".
That hit me pretty hard.
I went many years without one, when that woman hit me with her car and my head hit the asphalt.
It took me several months to shake the cobwebs.
Hopefully Shields will be ok.