Gastro-intestinal "discomfort" is one of my first pregnancy symptoms, too. And it subsides toward the end of the first tri, comes back late second tri through the end.
I find that making sure I drink enough water helps a lot. Because I find that if I'm eating what I'm craving, it sometimes (often) is either salty or spicy or heavy...like loaded pizza. Not easy on the digestive tract. And it helps it pass and helps get the salt out of my system, which I find gives relief.
And making sure you're eating fruit with every meal and once for a snack--that's my threshhold, yours may be different, but if I'm not doing that, I am hurting. And an apple a day--a whole apple, skin on--really does keep my body in balance for whatever reason.
Sitting up straight is important, too, because remember all your innards are getting squished up and into spaces they don't usually inhabit so your body can have room for the baby. Slouching can squish even more and make it worse.