What Do Constant Throbbing Pain In Lower Abdomen Suggest?

I have A sort-of throbbing, but constant pain down on my lower right side, kind-of between my abdomen, & my pelvic area. I do, & have been taking strong prescription pain medicines for a bad chronic lower back condition, of different prescriptions for the past 7 years, when the condition was first officially diagnosed. I admit that I have some fears as to what this may be!! Is there a major organ in that area that would be affected by medications over a period of time?