What Causes Severe Pain In Lower Back After A Partial Hysterectomy?

Hello, I am 41 years old, had a partial hysterectomy in 2004. I still have my left ovary. About 2 weeks ago I experienced lower back pain which left me unable to move. I do not have history of back pain, nor did I lift anything heavy or do anything out of the norm. Pain subsided within a week, but than I received lower left abdominial pain. I cannot sit without experiencing sharp pain, nor can I lay on my left side. Only comfortbable position I find is laying on my right side. On Friday, I than started to experience some numbness and a bit of shooting pain down my left leg. I went to the ER yesterday as the pain has become unbearable. The ruled out kidney stones with a CT scan. They found a a cyst that they say could be the cause. I plan to followup with my doctor this week, but curious if this sounds right. Could a cyst cause all these symptoms I am having? Thanks for your time...