No chiropractors are not allowed to prescribe medications unless they are also a medical doctor. A mri is probably needed of your back otherwise you are taking the risk of permanent damage and pain. You need to find out the cause of the pain not just treat it. An adjustment may help but if the pain continues or gets worse please go to your doctor and request a mri. You could have a pinched nerve causing the pain and trust me they can get worse. Best of luck to you.
I'm going to get an appointment with a medical doctor for an MRI and hopefully immediate relief.
Good I hope you get relief soon. When you were injured did you report it at work? If so they should pay for the expenses. Best wishes.