I have very painful back pain.

Many causes: There can be many cause. Muscle, bone, kidney, and even abdominal causes. If pain seems to be worse with movement then probably muscle skeleton pain. You should see a doctor because many possibilities.

Careful: We need more information. Severe back pain can be serious. There are many potential causes. If you have had no injury and you have persistent severe pain, you need to have it evaluated. If you have fever with it you need to be seen. You can try ice, heat, and ibuprofen, but if your pain persists then you need to get in for evaluation.