Mom finds Condom box

I am a 16 turning 17 next week(: I am afemale who really loves her boyfriend. He is a really really great guy, and a good time into our relationship we started having sexual intercourse. We do use condoms and spermicide, we do try to be as safe as possible. I even am getting on the pill  December 26th. Our parents do not agree with teenagers being involved in sexual activity. Yesterday, his mother found an open box of condoms in his bag, and contacted my mother. I did not tell her we were having sex. We know if we told our parents we were sexually involved with one another, there would be consequences. There are even some consequences now. Like when hanging out, my brother has to be with me, the basement door has to be open when we are down there...etc...I am extremely lost and feel very uneasy in this situation. My boyfriend is not taking it well, he believes we should not be treated like children. I need some help and advice. Thank you. (What we said for the lie was, a friend left them in his car, and he put it in gis bag to return to him at school, but his friend was not at school that day)