I believe that stone formation is the result of biochemical imbablance in the body(the result of poor diet, drugs, lack of minerals, etc). There are many factors, but a lack of bile acids or an overload of cholesterol maycause stone formation. You may also have a large harder stone that is stuck in the gall whichmay be giving you an attack. If the stone is to large and the flushes do not get it out of the gall, you amy need to consider the convential method to get rid of the pain. (which would be my absolute last resort) Try all the herbs etc if you can bear the attacks. I'm not knowledgeable enough to assit you with the herbs to try to break up stones.
I would try a flush and lay on my right side briefly (until you feel the gall contracting) and then my left side. This would let gravity help get the stone near the duct opening and you may pass it.