question: I started having sharp lower back pain on the left side about a week ago. The next morning the pain was on both left and right sides. I went to our medical clinic where the doctor hoped it was muscle spasms. Prescribed valium and Tramadol. I took both and laid down about 4 hours later the pain got worse and radiated to my sides and abdomen. My medic took to me the ER where they did a CAT scan and ruled out Kidney stones. But my blood work showed CR levels at 1.8. After 2L of fluid they had me come back the next day and my CR was still at 1.6. Yesterday I met with a internal medicine doctor who said he had no idea while my levels are high and it could be something I ate. He also said my back pain could be from the mattress I sleep in. I only woke up in pain a few times all other time it comes on when I m up doing things. I am currently deployed and just looking for a second opinion. I read that in order for CR levels in your blood to rise one of your kidneys has to be functioning at 50% or less if this is true then should my doctors be doing something?