I have read most of this thread, I am at work and have to keep logging off, I found it after googling symptoms I was experiencing.
The last 24 hours have been totally hell, I use to suffer from this in my mid 20's and I haven't had it for a while (I am 32 now) and just assumed it was bad diet and stress, both of which I don't really have anymore.
The night before last the stomach cramps started up again and the pain was terrible, then yesterday the vile tasting belches started and stomach ache was on and off (I came to work anyway) so I took a load of pain killers. I got through yesterday having to go to the toilet every half hour or so as I have diarrhoea. I went home last night and the symptoms had calmed down a lot. I managed a bit of cereal for my tea and went to bed (the belching continues). I woke in the night again in so much pain, extreme diarrhoea and vomiting. OMG the vomiting was the worse, every time I was sick I had the taste of sulphur in my mouth. I am not sure whether the sickness was due to the stomach pain or the vile taste. I got through the night and have come into work. I am a bit nervous about burping, but so far all I have tasted is the smothie I managed to have for my breakfast, so I think (hoping) it's gone now (although I still had diarrhoea when I woke).
I am a veggie, so I know it's not a meat thing that has caused it. Someone mentioned about it being different sorts of fruit not digesting properly, well I had eat quite a bit of dried berries, along with fresh berries and fresh fruit. I do normally eat a lot of fruit though, although I had properly eat more than normal the day before yesterday.
When I use to suffer with this I didn't eat a lot of fruit, so I don't know if it was the fruit that caused it.
The pain was unbearable and I could even cope with that, but the sulphur taste is rank.