I am 15 and will be going into 10th grade when school starts up, but I still havent had my period. My mom started when she was 12. I have had discharge for about a year and a half and I have all the signs and everything else. I ve always been pretty thin and small for my age but I don t know if that will effect when I get my period or not. I m also really active in sports like tennis, dance and ice skating. When I went to my doctor recently, he said that if I don t have it when I m 16, they ll have to see what s wrong. And I really don t want to have to do that. So...why haven t I had my period yet? Is it just because I m small?