Since my ana titer of 1:320 came back my knee has been swollen and leg now my back hurts when i breathe in and out do i have a immune disease ?

Only a screening: An "ana" is a blood test used to screen a person for the possibility of several autoimmune diseases. It is important to remember that this is a screening test and a positive result only indicates more testing may be warranted. No blood test is perfect, and getting to a diagnosis is usually much more complex than drawing blood and looking at a number on the results report.