Hi,
Do you have any other symptoms other than pain?
Have you undergone any Xray, Ct scan or MRI of lower back and head?
One sided pain does suggest a nerve compression or a pinched nerve.
I would suggest you to consult a neurologist as soon as you can and undergo a complete neurological examination and some tests. Take care!
Are you taking these meds for herniated discs, severe car accident? What were they initially prescribed for, I'm betting not the headache. You can actually get a narcotic headache from the pain meds. I have no idea why - they see it a lot at the hospital. The correct dose of demerol for a post surgical procedure will give pain relief from surgery but after a few doses, a horrible headache starts up. They can then switch to vicodan ect... Have you had an MRI - need a diagnosis to answer more.
One thing to think about morphine is very constipating. Sorry to ask but are you having a healthy bowel movement everyday. Chances are not because you can't be getting adequate excercise. That will really aggrevate low back pain.