Well i should have been on the pill :O:O?

Well me and my ex-boyfriend chris had a month ago but he already has 3 kids and he is 15 i am 15 too (i should have closed my legs) i don't know if he was wearing protection and just last week i found out i was pregnant :O the only people i told is my best friends chloe and brooke chris obv and my fab auntie deb shes my god mother, but my mum and dad don't know but my big sister has had a baby but mind shes 22 and she Had him 2 months ago but my mum and dad will kill me they really will so my auntie said i could move in with her if my mum and dad will throw me out i know i am 1 month along and i am going to keep it so don't say i shouldn't keep my child because i want my baby but chris doesn't want anything to do with the baby as well as the other 3 at age 15!! i cant really say anything about that because will i am pregnant so how should i tell my mum and dad what do you think??