oldest daughter

i have a 15 year old girl who actually is a very good kid she doesnt complain that i have access to her accounts and phone she doesnt mind that i need to know where she is when shes out she talks to me about every thing. so when she said mom i would like to go on birth control i didnt freak out shes not dating she just says she wants it now just in case. i was 17 when i had her and i was to scared to ask my mom so for her to come to me shows she mature and responsible.