You probably did not do much harm to the cleanse itself. The membrane of the little lemon bits that are not strained out are largely cellulose, and humans lack the enzyme to digest cellulose. You might have experienced some degree of fullness if you ingested enough of the bits, but I doubt if you added much in the way of calories or excited the digestive system. You probably just added a little extra fiber to help push out waste. Still, now that you have removed the old remaining bowel contents, its probably a good idea to strain the juice. you do not have to start over, but if you wish, add a few extra days for additional cleansing. I always liked to use the finest strainer I could find and braek up those little bits of pulp to get out all the juice I could.