What Causes Right Abdominal Swelling?

I have pain in lower right back and numbness in lower right abdomen and upper right thigh. Now I also have swelling on the right side of my; abdomen. Had severe pain in back four days ago. Went to ER, had CT and they diagnosed kidney infection. put me on Cipro...went to my doctor yesterday and she said the numbness was a pinched nerve which should clear up. Now I have the swelling in the lower right abdomen, quite pronounced. I am a fairly healthy 64 year old female, no diabetes and no high blood pressure (130/70) What could be causing the swelling in my lower right abdomen? Thanks