My opinions on bottom surgery is a surgery to complete the esthetics side of things, otherwise you are female or male regardless how you are mapped.
In theory, there is never (and I use the term loosely) a time in your life where you are uncertain of your gender.
It might seem, like it. However, between how you feel as a child and at this point in time is how you felt all along. It's up to you to really realize that rift in your lifetime that this is the reality.
There is no escaping it, only a selected handful grew out of it completely, while some just took time.
While (most) of us are mapped a certain way, we will tend to go full out and esthetically make our body's match how we feel. A lot of people have their ups and down views on this however it basically comes down to YOU.
How do YOU feel? Are YOU sure you want to do this? Do YOU think this is right for YOU?
I personally am BI but have a stronger tendacy towards men, and too me to have something dead between my legs that I can't use regardless due to hormonal effect is a nuissance and I need it to be gone.

-Sara