your entire point of view of the world shifts. you start to think of everything with them in mind and they're always there with you even when they're not there physically. You always want to know what they're doing, out of genuine interest. You truly care about their feelings and desires just as much as your own, if not more! you just know. Art and music start to make sense, everything is magical. Falling in love is the best, but you shouldn't fall, you should love, because if you fall too hard you might break some bones.
Easy, follow your heart... I'm sure u know when u dislike someone... love is only complicated when you put a time frame on when u feel like u should feel a certain way... sometimes love is found the first week... don't let society tell u when to love someone... u know already... best wishes love!!