From what you are describing, it sounds like you had a successful flush.
My opinion is that all the foul smelling matter did not belong in your system and better out than in.
Most people would suggest colon cleansing before attempting a liver flush, and of course since you've had surgery affecting your digestive tract, it seems wise to consult your doctor. Is it safe for you to be ingesting large amounts of oil and grapefruit juice ? I do not know the answer but I bet your doctor does.
I think the general rule with Liver Flushing is you have to do it around 8 times to see the positive benefits.
Me personally, I've flushed 15 times. My symptoms are better but still present so I have more flushing to do !