Typically, pain is the body's way of saying "STOP what you are doing NOW!"
Since you are so constipated and several days worth of food in the colon DEFINITELY engorges the colon and presses it into the liver/gallbladder, it would make far more sense to "unsquish" the gallbladder rather than trying to force things through it when it's squished (and/or killing crittersthat would add dead carcasses to the clog).
I recommend you do a thorough Colon Cleanse first. If while doing the colon work, you find your body needs to flush, then you can always do that while you're cleansing.
Okay, really, I've got to get back to my forum - you know where you can find me if you'd like more assistance :)