welcome to Health care magic.
1.Next time please mention the age, as the advise will be changed.
2.First thing you have to analyse the cause of the pain, as you already tried medication and it seems not working.
3.If you are my patient i would start with a x-ray
lumbar spine AP/LAT views, depending on the finding, if required
MRI will be indicated.
4.The treatment start with simple x-rays to interventions as required.
5.
Back pain exercise please follow this link.
http://www.nhs.uk/Livewell/Backpain/Pages/low-back-pain-exercises.aspx
6. If it does not work then see your GP and get investigations done.
Hope it helps you. Wish you a good health.
Anything to ask ? do not hesitate. Thank you.