I am feeling pain on the upper back on the left hand side and on my lower back around my waist. what could be the cause and how can it be treated?

Doctor can examine: Some common causes of lower back pain include: back muscle strain, back ligament sprain, fractured vertebra (spondylolysis), slipped vertebra (spondylolisthesis), herniated disc, spinal stenosis, spinal arthritis, urine infection, kidney infection or stone; tumor in the spine, kidney, or elsewhere; fibromyalgia, etc... With such a long list of possibilities, one's doctor can evaluate.