Dieting first week hunger?

I recently started dieting on Monday morning. I ate breakfast for the first time in awhile, drank plenty of water and watched my portions. Got home from school and did 20 min of the bike and lifted weights. But there is one problem...I'm hungry. Is this normal for the first week? How do I keep myself from eating? And how do I understand the difference between being full and being bored? I used to overindulge all the time since I was little. I'm now 16 and 199 pounds 5 foot 8. I want to get that lean tone body. Any tips on staying full, exercise, exe...thank you for your help :)