I just lost 30 lbs but now im always hungry?

How long did it take you to loose the 30lbs? If u lost it too fast, it's the way your body trying to hold on to the weight it once held. It's built-in our genes to survive in famines.
You have to give time for your stomach to shrink back to the original size, mean while try to drink lots of water and low carb veggies. Good luck.

Congrats on your weight loss!

To fill myself up, I try to drink a full glass of water before every meal and I drink water while I eat. Hot tea (no sugar) also helps fill you up because the steam expands your somach, somthing like that.

AND I eat 2 cups of lettuce with lunch and dinner.

You're hungry because your eating the way you should. Fruits and grains don't have that much calories, and calories are energy. Because you're eating healthy, you'll have to eat more of that food to have enough energy for the day. You shouldn't put back on the weight. Just keep doing what you're doing, and make sure you eat other foods groups, not just fruit and grains. Eating smaller meals more often is actually recommended by doctors and specialists.