My ana, crp, esr, RF, are all normal, suggesting no autoimmune issues. However, oral Cortecosteroids alleviate ALL my chronic pain symptoms. Topical, inhaler, and nasal cortecosteroids are very helpful addressing those specific areas. What's happening?

It feels like systemic inflammation is causing all my chronic pain issues, or at least playing a role. I took oral cortecosteroids for one week as a test (Dr approved, surprisingly), and my headaches, breathing difficulty, stomach issues, fatigue, brain fog, and more all decreased significantly. This made it seem like I had autoimmune issues, but my basic tests say I don't. What could be going on? Could the steroids be helping something other than auto immune issues?

Can the tests, ana, crp, esr, RF, have false negatives?

Thanks!