Based on your answers, some of the most likely causes of your back pain include
fibromyalgia
disk disease
sciatica
spinal stenosis
ankylosing spondylitis (or related conditions, called spondyloarthropathies)
muscle spasm or strain.
More than one of these may be present at the same time and other, rarer, causes are also possible.
While over-the-counter pain medicines, a heating pad, and rest balanced with activity may be helpful, it is important that you see a physician to evaluate these symptoms.