So scared of gender disappointment

So i am 12 weeks going to find out if it is a boy or girl i really want a girl ever since whenever i always wanted my first to be a girl and hubby wants a boy not shure why but i am weird when ever i changed my little cusins dipers i got confused with the 3rd leg. Like i have to pick do i want to cercomsize him what age should he go hunting i dont have a 3rd leg how do you pee like i dont know i might be a bad mom if i cant figure it out ahhhhh i think i am going crazy