At C6-7 you have a disc buldge that is exerting pressure on the thecal sac. That sac is filled with fluid to protect the nerves of the spinal cord. You have mild pressure and indentation which can cause pain if impinging the nerves. MR is imaging the supine position. Standing, sitting and especially sitting leaning forward increases the pressure.
So you have the nerve bundle and then you have the nerve exits. The nerves exit the spinal column through a small joint at the part of the vertebra on each side. When those spaces narrow as the do when the discs buldge or the vertebra collapse, the nerves can get painfully pinched. you have several cervical areas that could be painful because of that. Some of those neck pains might be muscular in origin
Physio is great.
I think chiropractors know the most about body mechanics. Even if you don't like the adjustments, the assessment is so worthwhile.
Take both.
I'll send you some links because all the words don't make it easy to visualize

You can greatly lessen your pain with good body mechanics.
But I still think you should see a pain specialist because of the L4-5 disc.

I've been in theater for a few discograms, but haven't had one. They are done to ascertain that the disc is causing the pain before microdiscectomy. I have bulging discs but no herniated discs.