Coffee! You can drink coffee????? ACK.... I get sooooo sick on coffee.

I will add that I had terrible iffy stomach, with pain, for years.
(I have a GI congenital defect which I always blamed for it)

1) you can have a sluggish gall bladder, and I have 2 things that work for that very well. Mine was so painful...and the tests showed "normal"... etc. Contact me for my useful hints...

2) This is something that can be hidden for a long time...giving IBS symptoms. It is fructose intolerance. This can cause gas, cramping and stool frequency. It comes and goes depending on what you eat. There is even fructose in some salad dressings!
Once you go on an elimination diet for fructose (both fruit and high fructose corn syr), you can have relief within a week.
A hint would be if you get upset by apple juice/cider, or apples, then you most likely have this. Pears it turns out have the highest fructose of any fruit/serving, and I used to throw after eating pears! After 2 yrs of eliminating fructose I can have now an orange a day. Small amounts following regular food which dilutes it etc. I have seen reports on the net that fructose intolerance can be diagnosed as IBS.
http://ibs.about.com/od/symptomsofib1/a/fructose.htm

This article is an eye opener, and reveals how common this really is!