Neck weakness / muscle spasm

Hi, I had a whiplash last year, followed by a blow to the top of my head 5 months later.
The whiplash had almost resolved, but the other injury (on top of the other one which was still fairly recent) has really impacted me. I’ve had MRI’s, MRA, xrays which don’t show any major abnormality.
I didn’t start physical therapy right away after the second injury because it was so painful and I was waiting for new MRI, etc.
I’ve had a little acupuncture, some chiro and now myofascial work with trigger point therapy and some more traditional PT.
It’s only been about 1.5 months since I started this more recent bodywork on my neck.
I’m learning strengthening/stretching exercises, etc.
I’ve seen a little progress but it’s frustrating when you’re so uncomfortable.
I don’t have much pain anymore (thankfully) and my range of motion is actually pretty good, but the deep muscles in the back of my neck feel really tight at times and when I’m upright (walking) it feels like my head is sinking down on my neck (like there is very little muscle there to cushion).
I think my muscles have probably atrophied some and the right side of my neck is somewhat hypertonic (bigger than the left) so I’m trying to balance that out as well. Any hope for a full recovery, how long (I know everyone is different) and am I doing the right things? Thanks