Some of what you describe is how anxiety manifests in me. I agree with ruh roh in terms of trying to find an activity that soothes the system in some way. Lately, I have found weeding my yard has allowed some of that soothing by activating a different element of my OCD like traits. Not sure if it is healthier but my body is calmer.

Also, if you really feel it is the only way... in my neck of the woods there is an imaging center that doesn't require doctors orders but you have to pay out of pocket. I'm not sure if they'd do brain, it's mostly for sport injuries - knees, hips, back to help determine appropriate physical therapy.