It's hell in limbo....
Hello Unsure...

Oh how I wish I had some great words of wisdom on the subject of not having a name for what ails you. How does one manage the unknown? It would be damn difficult!
Try not to be too hard on yourself. Who wouldn't feel the frustration!? What can you do about it? Well, not much more than to carry on. You know you'll get there, but the wait can be painful!
I read an article a while ago that said, "...waiting for a diagnosis is more stressful and causes more anxiety than the diagnosis..." If I may borrow a term from the young people...
DUH!
The late Jean Kerr, American author, went to 26 doctors before she got a diagnosis. She had MG. I don't know that I would have had that tenacity.
We are experiencing the same wait times here. It's global, and given the demographics, it will be a challenge for quite some time.
What is helpful to me is to rather than think,..."What if..." I'll say, "What's my plan b?"
A man on a thousand mile walk has to forget his goal and say to himself every morning, 'Today I'm going to cover twenty-five miles and then rest up and sleep.”
―Leo Tolstoy, War and Peace