Abdominal pain

For the past 2months I have had minor sharp pains in my stomach across my navel. The pain only occurred periodically around once or twice a month and only lasted about 2days at the most...but once or twice during that 2 day period.
I had decreased appetite for the past 2 weeks. 4 days ago the pain returned but it was continuous and became mild. 3 days ago the pain became severe and also moved to my right side, lower back (around the kidney). Sometimes the pain in both areas would co-exist or would alternate between the sites. This pain lasted for around 50 hours and the majority of the pain was in my lower right back(kidney area). I went to the ER 2x and they did urine, blood tests, and ct scan. The Dr's stated that nothing came back irregular. After the 50 hours of the severe pain..the pain became lessened to moderate (severe upon walking and to the touch) and has moved to only the right side in between my kidney and right abdomen area. I have re-gained my appetite slightly.