What does it mean to think about someone all the time?

I have this guy that i think about non-stop and i really like him. Every time im thinking about a guy it turns into thinking about him. I miss him constantly. We don’t see each other or talk alot at all but when we are together its just really nature and sweet. And i dream about him alot too. I’m just wondering what all this means because i’m not sure if im in love or just miss him alot.