I've been going crazy but it's like she doesn't care?

so it's my BESTEST friend birthday tomorrow and all day ive been talking about ti because I;m so excited i don't know why its just that's shes my best friend and she knows im really excited. i posted a video saying happy birthday on her facebook wall andi have been talking about ti all day and at 12 midnight im I'm gonna give her the best happy birthday ever and she knows that but she doesn't seem too excited like shes giving me one worded responses and like she acts like she doesnt care idk I always come uassumptionsumtions but shes being really weird. what should i do?