Talk to General Physician on Back Muscle Spasm

It has been more than a month since experiencing severe pain and stress in back muscles. Upon consulting a local doctor, a painkiller injection & Neb***F*t was prescribed. After taking the medication for 10 days, the pain and stress was still there.

Upon visiting an Orthopaedic specialist, who was not available at the time, their junior conducted an X-ray examination and diagnosed it as "muscle spasm," recommending rest along with muscle relaxant medication. Despite taking six days of bed rest and medication, the pain remains almost unchanged. What should be done next? Whom should I consult?