Self DX or not, I think being critical is always good. I mean they wanted to diagnose me with schizophrenia, I had to really fight that.

"But you DO hear voices!"
"No, I do not."
"The VOICES told you to say that!"

Sigh.

Or "You only have Sjogren's, no other autoimmune!"
"But my issues started years before I got dry eyes!"
"Oh wait.... then you have lupus too!"
"Eh... okay?"

They are not aliens or perfect. Sometimes they too just guess. My guess is usually better.