Bowel Problems and Acid Reflux - very concerned!

aquachic

I've been having a lot of gastrointestinal issues over the last year, and I haven't really been able to get a descent diagnosis. I'm 25 and female. It started last year when I woke up with chest pain that just wouldn't go away. After having an abdominal ultrasound, chest x-ray, endoscopy, and ekg, it was determined that I had gallstones and mild acid reflux. I had my gallbladder removed, which helped a lot with the chest pain, but not completely. Now instead of having constant chest pain everyday, it's more mild and about 3 times a week, but sometimes it hurts so bad that it causes my left shoulder to hurt as well! I'm told this is being caused by acid reflux and a sensitive esophagus. But, I a taking Nexium 2 times a day and my endoscopy only revealed mild irritation, so I am having trouble believing that acide reflux is causing all of this for so long.

In addition, to the chest pain, I am also having bowel problems. I was diagnosed with IBS at the age of 5, which up until last year was constipation predominant with the same pattern of symptoms. Then, about the time that the chest pain started, my symptoms switched to intermittment diarrhea with floating stools. Also, I have had a lot of gas and belching, and in the last two months I've started having mild pain on my upper left side just under my ribs....actually it isn't so much pain as soreness and a feeling that something is not right.

I'm very concerned that I've been misdiagnosed and that the doctors are missing a serious condition like pancreatic cancer. I've also considered the possibility that it could be something like celiac disease, but the doctor's keep insisting that it's just IBS and acid reflux and don't want to look further. I know that the chance of pancreatic cancer at such a young age is very slim, but the floating stools and other symptoms worry me...what could cause these symptoms?

I should mentioned that I've not had any weight loss...actually some weight gain.. or any other symptoms.

I would really appreciate any suggestions or insights you might have, because even I'm very worried that I have a serious condition that's being overlooked!