I would say that this is premature. So many things can change and will change within the next few years. Granted things are always changing but I think the most profound changes happen from about 18-21. At least in my experience. I was in a serious relationship with this guy from the time I was 15 until I was 19. I got pregnant by him, we moved in together, and everything fell apart. To keep it short, the things he wanted out of life were very from the things I wanted. We ended up being miserable toghether which lead to bigger problems. Finally he left me with a baby, a stack of bills, and no job because I had just had our son.
Basically what i'm trying to say is, if you love each other , take your time. Wait until you're old enough to move in together. Beleive me, that's when you'll really get to know each other. And then take it from there. There's is no need to rush a good thing. if it is meant to last, it will last.