Welcome to HealingWell!
Has your doc done any non-invasive tests to better help pinpoint your problem? Blood tests or stool tests, maybe even an ultrasound?
Upper left quadrant pain can be any number of things. It can be just gas - which absolutely can be caused from IBS. In which case you might want to try Gas-X, Beano or peppermint capsules. It can also be a problem with your Pancreas or Kidneys. I think even pneumonia, gastritis and hernias can cause it too.
Do you have GERD? Have you been tested for H.pylori?
Sorry I'm not being too helpful. You might want to go back to the doc (or find another) to do more tests. And also, don't worry about
being scoped. It really isn't bad. The worst part is drinking the laxative... the easy part is actually being scoped. You would be comfortably sedated for that.
Hopefully someone else will be around shortly to give their input as well.