Hi Pacific Girl,
You can do the salt water flush or take some Epsom Salts . Or, you could do an enema, anything to get the bowels moving again. After a flush, because of the diahrea, you are dehydrated and need to be drinking lots of water to rehydrate. If you drink distilled water, add a quarter teaspoon of real Sea Salt to each glass of water to help put back the electrolytes.
The upper back pain is most likely from the liver. It was in my case anyway. I found a coffee enema took the pain away.
Wishing you a full toilet bowl. :) Omie