Since this is an emergency, you may want to consider drinking a cup of very strong coffee and use a couple glycerine tab suppositories from the drugstore.
Then you can do the gentler and safer interventions: deep enemas (everyone should have a 2-quart bag or bucket! It's an essential tool for maintaining and restoring vital health.), milder fruit laxatives like prunes, rhubarb, Triphala; ground flax seeds or flax seed tea.
Until you eliminate, you should fast and drink nothing but warm water and broths and Cleansing Drinks (MC + ACV) to offset the poisons.
the problem with the Master-Cleanse
is that it does not give instructions on how to wake up your digestion after putting it to sleep for so many days. This can lead to all kinds of problems like the one you're experiencing now, sigh. There's a way to come out of hibernation and it doesn't mean eating cold, raw foods or bland foods. You have to eat cooked and spicy for a few days.