Birth control for teens?

Okay so I'm 15 and I've been in a relationship for almost 2 years now. For the duration of us being together my boyfriend and I just used condoms (haven't had a failed thankfully). But I wanted to go on another form of birth control too to make sure that I have a back up in case a condom fails (I LOVE babies, but I am NOT ready to be a mum just yet!). What do you think would be best for a teen? I was thinking about an non-hormonal IUD because they're long lasting and I don't really like the idea of hormone birth control but I'm not sure.