You might want to try Canada Dry ginger ale. It's one of the few brands made with real ginger, a natural anti-nausea agent, plus the carbonation helps. I pretty much lived on the stuff my first couple weeks.
Other natural anti-nausea/anti-gas remedies safe for pregnancy include peppermint tea or candies, fresh ginger grated into hot water or ginger candy, or anything with lemon -- tea, drops, hot lemonade, etc.