Pressure/Tingling when I turn my head

I was in an automobile accident and ended up with a herniated disc, 2 bulging discs, and one torn annulus. It affected C4 - C 7.
One year after the accident, I ended up in surgery where they fused the herniated disc C5-C6.
The terrible ache in my right arm was resolved immediately. The tingling is still an issue.
One of the things that was present before my surgery and after my surgery is this.... When I turn my head to the left (this was also the position my head was in at the moment of impact), I get a really weird feeling in my head and right arm. I feel kinda dizzy or light headed, but it feels like pressure too. I also feel like I could put my right arm to sleep with my head turned like this. Also, the tingling on the top side of my right hand that spreads down to my thumb and index finger is still no different than before surgery. My right arm and hand are also still weaker than my left, and still feel kind of "fumbly"
Is it possible that I have a brachial plexus injury? During the accident, my head was turned as far to the left as possible at the moment of impact, so basically I hyper-extended my already hyper-extended neck. The day after surgery I could not even touch the whole right side of my neck or top of my shoulder because it hurt so bad.
I seriously don't want to have to go through another surgery, because the last one left me with a paralyzed vocal cord, but that's a whole different subject....
Are there tests to determine if this is what's causing these weird sensations in my head and arm?