MoviPrep for hemorrhoids?

my doctor had prescribed me with MoviPrep to help relieve my hemorrhoids but did not give me clear guidance. It reads on the instructions that i must not eat solid food before my examination, however i am not having a colonoscopy so do not understand what i should be eating. also, after my first dose this morning i am now suffering with bloatedness and sever abdominal cramps, does anyone know how to help this? many thanks.