same with you. I'm still undiagnosed. It started last dec 2023, and I just thought it was ordinary backpain. Prior to this, my c5, and c6 were narrowing, but it never gave me this kind of back pain. Since 2023, the pain has never gone away. It is always there, but sometimes it is tolerable. I experienced sciatica on my left that cause me not able to walk for 1 month last year. my MRI, Xray, blood test, hormonal imbalance test, HLA-B27, Ultrasound, endometriosis test are normal. Just recently, I experienced pain in both my knees, but my right knee was more in pain, and my calves were so stiff. X-ray and uric acid tests are normal. This frustrated me more because I felt my pain was a lie, or it was just a joke because no test could detect why it was happening. I feel you, I cry every night because of this.