weight loss with abdominal pain

I started getting pain in my abdomen few weeks ago. I also lost my appetite and lost some weight. After an intense night of pain in my lower back and right side, I went to see my GP, suspecting a possible kidney stone, but a CT scan showed swollen lymph glands, but nothing else. My physician put me on antibiotics, on the off chance that it's Diverticulitis. So, what could it be, does anyone knows?

Well, I had similar problem weight loss with abdominal pain. I waited for few weeks before I went to see a doctor. Well I went to see him when I had sharp needle pains in my abdomen and a chronic pain in my lower back. He concluded that it was because of the inflammation in my small intestines, due to Celiac. It took several months for the back ache to subside.