What Causes Cramps And Lower Back Pain After A Hysterectomy?

Hi, yes I had a partial hysterectomy on5/4/11 and I have been experiencing cramps now for a couple of weeks. I've had other complications since the surgery and even mentioned the cramping and asked the drs. at the ER what they thought, but was shrugged off at the time. Since then, I have been experiencing increasing lower back pain ( I thought it was due to a tumble a took recently, at first), increased front cramping, something "akin" to bladder pain, even more than normal difficultly with trying to urinate and not getting much to come out. What are the possible reasons for these combos of symptoms? Oh, I also had a bladder sling/bladder support done, repair to a rectocele & cystocele, and repair to a relaxed anal sypixnter muscle plus only they and God knows what might have been done but that what I can remember been told after the surgery. Thanks for any help.