Searching for answers

About 10 months ago, I began experiencing several unusual symptoms, that to date, we have found no causes. Random waves of nausea with dry heaves, random waves of dizziness, unintentional weight loss, itching on my hands, and the taste of various foods being totally like garbage. Through many tests, we've been able to rule out brain tumor, alpha gal, Grave's disease. I've had head and neck CT, MRI w/wo contrast, multiple x rays, blood work (so many vials taken!), and consults with specialists of many different types. So far, nothing. They all agree it's not psychosomatic, but nothing is coming up. My GP feels it's most likely autoimmune, but there are so many, how does one even begin figuring this out?
I came across this site, once more in my foray of looking for possible causes. I'm hoping maybe my symptoms will be recognized by someone else who may be able to shed light or suggest possible causes that I may then follow up with my team. At this point, I feel my GP is at a loss. And frankly, even with a good medical insurance plan, the OOP costs of the testing is getting beyond my reach.
Thank you in advance for reading my post, and hopefully someone somewhere may know what exactly were dealing with.