Doctor is 100% certain - it's not the gallbladder!

I am having a most challenging time with a medical diagnosis. Thought I would post here to see if there were any suggestions I could bring to my doctor.

The onset: I was sick with a flu. Vomiting, diarrhea, fever and dehydration. The nausea was so fierce I couldn't keep water down so I saw my family doctor. She changed my diet from water to Gatorade and broth. This cleared up my nausea and I began feeling better. My mom started feeding me - bananas, berries, oatmeal and toast. I began to get a backache immediately after I started eating. It began in the upper right side, it's deep, penetrating and the pain went from a 4 to a 10 in three days.

Treatment: Three days after the onset of pain, I went to the urgent care clinic. Blood was taken and tested, and I was given x-rays and morphene. My EKG was slightly abnormal, but they ruled out a blood clot. Confused, they sent me by ambulance to the hospital. In the ER, this doctor gave me an abdominal exam, and the corresponding area on the front was much worse then the back. The pain probably originated there. I had a positive Murphy's Sign. An ultrasound was performed and he thought he saw a gallstone. A more thorough ultrasound was scheduled for the next morning, and I was released for the night. I returned, and they determined the ultrasound was normal. I was discharged to my family doctor's care. She sent me for a CT scan (Normal), and to an internal specialist. They tested for hepetitis and HIV, all negative. They speculated that it must be too much production of acid in the stomach. PPIs were prescribed, to see if they would make a difference.

Next Step: I have an appointment with a gastroenterologist to see more because the medication does nothing.

Meds: Tylenol 3 - which I am no longer allowed to take, although it's still necessary.

PPI - dosage was upped to one pill, twice a day.

I was on buscopan, but it's been discontinued as well by the internist.

I am 29, a young woman, relatively healthy, save being overweight. I never had any trouble with acid reflux, diabetes or any other related conditions, except high blood pressure, which has been resolved as a side effect of this pain.

The pain is strong, enough to make me scream. Movement and eating make it worse. I can only eat bland food, if it is a vegetable or a fruit or anything that's not completely bland, I get severe pain and diarrhea. I have been off work six weeks and counting. Any thoughts?