Hi,i fell down the stairs last week, i still have pain on my lower right side of my back leading half way up my back.what can i do?

Muscle Bruise: Sounds like you gave your muscle(s) a deep bruise (hematoma) in your back muscle(s) This may take a few weeks to heal. Deep heat will help along with Ibuprofen As a improbable but "possible" alternative, you may have fractured a rib in your lower chest in the back where it joins your thoracic spine. Treatment is same.....a xary may help diagnose!

Give it time: The answer depends on how bad the fall was. If you had significant trauma and were not evaluated it would be wise to be seen. If the pain is relatively minor and there is no significant bruising, or other symptoms, then it is likely to improve with time. It takes 2-6 weeks for a muscle strain to become non-painful. A strain should be at least 50% better in 2 weeks.

Hard to say: This could just be a mild soft tissue strain or sprain or a bone contusion(bruise). It also could represent a fracture. Before I would go forth with any significant range of motion or soft tissue program, I would make sure a professional examines you to make sure it's not something more concerning. I would seek more urgent help if the pains severe or you have new numbness or weakness in your legs.