Cholecystitis is inflammation of the gallbladder. Hanna is right about all the tests being off if you do a liver flush before surgery.
You can have pains around your waist when you have a problem with the gallbladder. Especially around the navel. It's not uncommon and throws the doctors off a lot. They only read the "classic" symptoms.
I really hope you decide to keep your gallbladder and clean out your body. It's once in a lifetime you have to do it with the Natural Healing Paradigm here, then you will be well if you just do maintenance the rest of your life. No diseases will materialize like stroke, diabetes, heart trouble, high blood pressure, high cholesterol. All of the ones that kill will not have a chance to get you. It's really worth the effort, IMO.
The problem with losing your gallbladder is that you have lost the alkalinizing organ of your body.