Is the left side the one you had decompressed, @stuuke? I’m sorry I don’t remember. It seems w/ the head pressure that there must be vascular or CSF congestion of some sort. It’s curious that’s not showing up on any of the scans. It would be good to get a second opinion on the scans rather than fully trusting the radiologist who wrote the report. I’ve had scans misread by highly respected radiologists. I think they look at so many scans in a day that unless something glaringly obvious jumps out, a “nuanced” problem, which could be causing symptoms, might be overlooked.
Your neck to shoulder/bicep tightness might benefit from some of the postural strengthening exercises @vdm has posted in this thread: List of my favourite resources on YouTube to learn anatomy
Tinnitus, especially constant, is a tough one. I’ve had tinnitus all my life but definitely have it worse in one ear now. I know it’s sometimes related to vascular compression but not always. Your autoimmune issues sound like no fun. Digestive could be related to vagus nerve as you know. Alopecia is also an oddity. Here are some vagus nerve exercises a friend sent me. I haven’t tried them yet but she said they’ve been tremendously helpful for her.
Everyday Mindfulness and Movement for Stress Management with Jenn Gebhardt.pdf (105.7 KB)
Resources for Everyday Mindfulness_Movement_Jenn Gebhardt.pdf (140.7 KB)