you sound like my mother..:)(saying: better do an enema as opposed to have wastes staying in the gut)
can you try upping your liquid intake to up to 7 pints? 4 pints OJ + 3 pints distilled water (slightly warmed)... mine is 2 pints OJ + 5 pints of distilled water, anything less than that equals zero BM the next day...
anyways, as MH says, you go with your intuition...
since the hydration did'nt work (which is the case for my mother most of the time).. I usually tell her, "ok, if you are going to do an enema, just dont tell me"...;)