What Causes Pain From Mid To Lower Back And Above Left Hip?

Having pain from mid to lower back that spreads above my left hip. Hurts to walk, bend, sit and lay down. I had an epidural 5 years ago and sat straight up because I thought they were done inserting the needle. Could that be causing the back pain? I have always had back pain since then but it was always very dull and manageable until about four months ago. Now I feel like my spine is going to snap at some points. Went to the ER and had an xray but nothing came up.