As far as I know the liver and gallbladder shouldn't cause pain on the left side. This sounds like a serious kidney problem. Kidney will affect both sides and can cause pain in the back. If you develop a fever make sure to take mega doses of vitamin c to control the infection. There are several kidney cleanses on this website. I would do the watermellon one pronto then follow up with some type of herbal one. Also make sure to drink at least 8 glasses of water a day. More if you are over 150 pounds. Please post back with results as your symptoms worry me.
I agree with the others do the parasite cleanse too but take care of the kidneys first or you may overwhelm them. And I also think 7 flushes is too much for the body to handle in one week. Especially if you are using any type of laxative with it, whether herbal or mineral.