My dad is gonna kill me!

Lilly • I'm 16. My boyfriend and I have been dating for a year now and we're taking about sex.
My dad took me to a "lady Doctor" the other day to get me birth control. I told him it's cause of my period and that is half true. So when we're talking to the nurse and she's filling everything out, she asks me "Are you sexually active?" And without thinking I say yes. I then turn to my dad, forgetting that he's there, and he's face is red and scowling. I'm over here freaking out cause my dad is going to kill me and my boyfriend. But he says,"Well you learn something new everyday. I hope your being safe." My jaw dropped to the floor! I was expecting him to ground me right there.