The last time I flushed (my third), I puked, too, about 3 hours after thaking the olive oil/grapefruit. I did not get nauseous at all on my first two cleanses, so what was different this time? Only thing I can think of, is that I had been relatively constipated for two days before starting the flush. If this continues, I may have to try a pre-flush enema or colonic to see if that helps.
Like you, I took the salts in the morning anyway (well, I took one serving). Surprisingly, I still passed some stones, but not very many. This flush wasn't a complete failure; I felt better after.