Hi and welcome to Healing Well!! :)
Basically IBS is a diagnosis of exclusion. They will do tests and if they don't find anything and your symptoms are consistent with, they will dx you with IBS. The most common IBS tests are fecal occult test (testing for blood in the stool), parasite testing, barium enema and/or colonoscopy (w/or w/out biopsies).
IBS is a functional disorder. Even though they don't see anything on your tests, it doesn't diminish the symptoms that we face with it. Your gut is more sensitive than the average person and they symptoms can range from annoyance to debilitating from one person to another. Its very important that you get the necessary testing done to get an official dx. Even though your symptoms sound right on the money for IBS, you need to make sure.
There is no cure for IBS. Fortunately a lot more focus is being done by doctors and researchers to find out the causes and treatments of IBS. There seem to be many different theories and many of them make sense. More and more studies are showing that there may in fact be a genetic factor on why we are more likely to develop IBS. My mother and grandmother have it as well.
Many people have found relief through probiotics, calcium carbonate, food diary (my personal fav :), etc. Many more will share their experiences. We are very glad to have you here.
Please let us know what the doctor says and take care :)
Co-Moderator ~ IBS Forum
~My reality check bounced