Autoimmune arthritis and stress test.

I have stiffness, swelling and pain on both feet , ankles and knees since January beginning. Went to the rheumatologist and had lab work, MRI. Labs are negative for everything except high inflammation markers and ANA positive. CRP and sediment rate higher. MRI showed inflammation and edema. The Rheumatologist said I might have autoimmune arthritis or inflammatory arthritis. It could be seronegative RA or psoriatic arthritis and prescribed me hydroxychloroquine 400mg a day as a trial to see if it helps. I have cardiac evaluation to check if the swelling is from the cardiac issues. I had an echo scan, venous ultrasound. The stress test is still pending. I have been postponing it because of ankle swelling and stiffness. I am able to walk at a slower pace around the house. I can't walk faster or run. Do we need to run on the treadmill test? Is it ok for arthritis patients to do the stress test? Can we walk slower on the treadmill?