It may be due to the spasm in the back muscles that is causing the pain or may be due to concretions in the kidney
that is causing the blood If it is tender it may be due to muscle have combination of
1. Pain killers such as Nuberol Forte twice a day for 05 days
2. Muscle relaxants such as Cap. Muscuril 04 mg twice a day for 05 days.
There is nothing to worry about you will be fine in a day or two
I hope I am sucessful in solving your query If you have more you can ask me.
Dr. Azhar Sattar