One very, very important rule is to take the p & b one hour away from meals on each side. You seem to have eaten 1/2 an hour after so then expect your liver to be overloaded with the cleanse plus the digestion. Always take the mix away from meals and remember to drink plenty after.
It is a good idea the first 2 or three times, when you get started to swallow a bit of senne after the mix to help with bm. At first the shakes tend to cause a bit of constipation. A laxative tea would also do the trick.
I had great success with the shakes. Here is another solution if indeed you turn out to be intolerant to psyllium (very few people are intolerant and you should really give it another try... WITH the laxative): //www.curezone.org/blogs/fm.asp?i=976144