I had the same experience with the early Sjogren’s test showing positive, but other tests were negative. My Rheumatologist began treatment with Plaquenil. It helped a lot and relieved many symptoms. They have since added immunoglobulin Infusions monthly and I continue to improve.
I already had a lot of damage throughout my body, but the other standard tests were inconclusive. One of my organs was starting to fail and it has stabilized.
I hope they can find a treatment that will help you and slow or stop any further damage. Best of luck to you.