I can understand where you're coming from.. Last tuesday night I had a killer gallbladder attack, that ended with me in the ER. Granted, I didn't have a fever, but the pain was tremendous. It did end up going away, and on friday I did my first cleanse. I just wanted to let you know that despite passing about 115 stones, there was no pain at all, as there is with an attack.
As long as you drink the Epsom Salts , you should be fine. It wasn't the most pleasant night otherwise.. I didn't sleep much, and I did feel some movement and sort of 'rumblings' in that area, as it was flushed out. I was pretty scared, like you.
Good luck to you, and let us know what you decide to do and how it works for you!