Huge Self Facial Self Esteem Problem.?

Self Esteem Problem.? - huge self facial

I am 16 years old. All my friends are all big, beautiful and always in the center of attention of children. So, who am I, ok not the nicest people in all. They have always asked about appointments would and called by other children. I never asked because I'm ugly. I am very strong personality, intelligent. I'm probably one of the most convinced that never met, but when it comes to it, I'm not. My sisters are still getting to appointments friend and I always say I'm ugly. It is really humiliating. Just because I have a birthmark on his face and takes a lot to me made. I can not eliminate all medical reasons and in the face that is absolutely beyond question. I really want, like I have to be sure, but I can not, and it seems incredible that something like this in my face and I did. Its enormous, not only up to my face, I hate. Please help!