What Is The Treatment For Delayed Puberty?

Hi i am 15 years old. i still have no started my period. im afraid i wont start till im like 18. my mom and sister started when they were 13 and i dont see why i havnt yet because i have been getting discharge for like 2 years and i have armpit hair and all ect. i am somewhat active though and im wondering also what a doctor does if you see them for not starting your period like what do they give you to make you start