need to eat more?

So I am now in the process of maintaining and have been slowly upping my calories for the past month or so. Basically, everytime I lose a pound I change my caloric intake by 100 calories. Right now I'm at about 1900 calories a day, (I'm 16, 5'5", 120 pounds, light-moderate activity) and while this is a lot of food, I find myself STARVING if I wake up in the middle of the night. I usually eat dinner around 6 (because I'm so hungry I eat breakfast early - around 6-6:30) and because I don't really go to bed until midnight, as I work late, I often go to bed a little hungry. But last night, for instance, I could not sleep, and I was so starving that I finally opted to consume something around 2 am.

My question is: Is this likely a sign that I need to

1. eat more?
2. eat dinner later? OR
3. eat more filling foods?

I'm hungry pretty much every three hours, but I don't tend to be as hungry after dinner (my heaviest meal of the day.) However, around the time I go to bed, I could often use a snack. The reason I don't snack then, though, is because I don't want the weight of the extra food to show up on the scale. My diet tends to be pretty carb-heavy though.... I stopped logging a while ago and thus stopped keeping track of macro-nutrients, and I log every once in a while to check. Yesterday was one of those days, and while it might not have been a completely accurate representation, I was at 65% carbs, 19% fat (I know I need more!) and 16% protein (I also need more.... though I usually eat more protein than I ate yesterday...)

One of the big problems is that my scale is a dial scale, and has a real problem with accuracy. And when you're trying to maintain your weight, that's not that fun. For instance, I stepped on this morning four times, and it read 120 twice and 117 twice. Nothing in between, which is really annoying. And while I'm inclined to believe the higher number, I'm not sure if that means I've lost weight, which would indicate that I need to eat more.

Sorry for the long post, I covered quite a bit, didn't I? Well if someone could please answer my question, I would greatly appreciate it :)

Generally speaking, if you feel genuinely hungry (as opposed to bored for example) then eat.  Make sure the majority of what you eat is healthy and 'whole' with lots of fruit, vegtables, lean proteins and other foods like grains with a good fibre content.  But don't sweat the percentages ... just try to appreciate good food, get plenty of variety and enjoy what you eat. 

Naturally slim people - or at least people that can self-regulate their weight - don't tend to count calories or eat exactly the same amounts each day.  They'll eat a little more one day because they're hungry or they have an occasion to celebrate and they'll eat a little less another day because they're not so hungry or they've got too much on. 

As you're only 16 you will naturally need more energy than an older person because you're still growing and developing.  You use up more energy doing 'light' activity than someone else older might.  Plus, you could be anything up to 150lbs and still be a medically healthy weight.  So don't be worried if you need more food... go with what feels right.