Nope I try to eat as usual. Anyways I think I even ate half of what i usually do due to Morn sickness, but baby still grow v well. If u ate more only you will get fatter haha. You only need to start eating slightly more during your 2nd-3rd trimester, and that is if your doctor says your baby weight is not growing enough. But then what I said above is need. Nothing to do with want. Just eat if you want, but in moderation! And choose healthy food!
Eat whenever you are hungry, while you can. I could eat normally in Week 5 till morning sickness kicked in which caused me to lose weight so dont think you should worry if you eat more than 3 meals as long as you gain weight healthily and steadily, same with baby. But can check with your gynae if it's ok to do so cos he/she will know best.