Well, it is quite common to be sero-negative for some of the autoimmune diseases...especially Sjogren's. I'm am completely sero-negative but my lip biopsy was very positive.

That being said, your negative labs could easily be explained by the medications you take...as many argue that immunosuppressive drugs alter antibody testing for Sjogren's and other AI diseases...and logic itself would agree.

Personally, you should be followed by a good rheumatologist and treated for autoimmune disease. Do you have (or ever had) the butterfly rash typical of Lupus? Or do you have dry mouth/eyes, typical of Sjogren's? I would hope you could find a rheumy to treat you clinically, not based on labs (especially since you take medications that can alter results).

Not sure why anyone would tell you that an autoimmune disease will 'run it's course and be gone'...that's ridiculous. Autoimmune diseases can wax & wane (as can symptoms), especially early in life and then reappear in the 3rd to 4th decade.

It's sounds like you have widespread dysautonomia. The treatments you are taking are good (I take the same combo), but maybe altering doses a little for better control. You should also consider something for the (likely) gastroparesis...like Domperidone. Much of dysautonomia is life-style changes and learning the tricks to keeping BP up, heart rate down, and stomach emptying better. There is a thread link below where i discussed some the things I picked up over the years to help in situations to keep from passing out, etc.

http://neurotalk.psychcentral.com/thread207110.html

I would suggest you get to a neurologist that specializes in autonomic dysfunction. There are other meds out there (like Mestinon) that are being used for this. I was unable to tolerate it (got immediate asthma attacks from bronchial spasms), but others have done well in some limited studies/cases.

You also need to see a rheumy and get better treatment of your AI disease, which may help the dysautonomia from progressing. You (likely) cannot fix the damage already done, but halting or even slowing progression is important. IVIG should also be considered.