D.D.
Water water water. It will helped with the back up in your digestive system. And it may help with the hunger pains - sometimes people's brains process thirst as hunger.
Start carrying some protein bars with you so if you get that gnawing hunger when you are out, you have something to eat that has protein in it, not just empty carbs like crackers and granola bars. And when you are at home, plan small meals.
When I was pregnant, I would eat a scrambled egg (just 1 was enough) for breakfast. Then I would make a PBJ sandwich to take to work along with a yogurt. I'd eat half of the sandwich at 10AM, the yogurt at noon, and the other half sandwich at 2PM. I also snacked on grapes all day long. So I made 1 'normal' lunch (sandwich, yogurt, fruit), but it took me all day to eat it so my stomach was never too full and it was also never empty. And I had a huge coffee mug with water next to me to sip on all day.
I had terrible morning sickness for the first 3 months, and doing a constant 'grazing' on healthy food all day was the only way I could get through the day at work.
Oh - Amber C mentioned vitamins! Check with your doctor for sure - the iron in your prenatal can block you up. I know someone whose doctor told her to take several kids vitamins every day (eg Flintstones) because they are high in folic acid but don't have iron. And my doc also recommended the stool softener (as Amber said NOT a stimulant laxative, a stool softener). Check with your doctor on both ideas if pushing water isn't enough.