How do I tell my mom ?

Mya
How do I tell my mom "I'm ready to have sex" even though I've already had my first time? I want her to trust me by telling her... But last time when I said that (when I was actually ready for my first time) She said I was too young, and just got into the relationship.. So that's when I took matters into my own hands and went to plan parenthood to get the birth control.. But then I got caught 👀😂 ... I told them I just went up there to talk, and I'm not using anything.. And I just wanted to prepare myself just in case.. That's when my dad got incolved.. And I just want to be able to tell my mom, without my dad knowing.. How did you tell ur mom?