Hello! I'd like to inquire about...I recently started experiencing pai…

Hello! I'd like to inquire about...I recently started experiencing pain in my lower back, maybe a month and a half ago. When I sit for a long time or even lie on my back, it starts hurting in my lower back. Previously, the pain was maybe 20 minutes after changing position. This time, the pain in my lower back has been for two days now...What is this related to? It hurts specifically the bone...What could it be? Why? Has anyone experienced this? Help!