I have IBS, and during my first 2 months especially, the pain was so bad I would end up in tears. Being my first baby, I was constantly wondering if it was baby related or gas (it was gas). I ended up taking Buscopan (recommended by OB) and charcoal (recommended by GP) every day, as well as extra fibre even though I already eat a high fibre diet. Honestly, I don't remember it getting any better until about 14 weeks, when it eased off a bit. Now at somewhere between 19-20 weeks, (depending on who reads the scans), I am still suffering, though only take Buscopan when I get the bad cramps, and just cop the gas bloating, as it has become a part of life. It definately gets worse if I reduce my fibre intake, though.
I know this probably wont help with your condition, but I find it reassuring to know that others are going through the same experiences I am.

Good luck