Can I get pregnant?

Is it possible to get pregnant 5 days before my period? This app says I'm infertile during this week, but I just wanted to make sure lol. We've been getting too carried away lately. It's crazy actually. It went from weeks of him not wanting sex or to do anything to me, to us not even thinking about it and him just diving right in. Lol Its been great but now I'm worried because we're usually careful and always use a condom..And I'm not on birth control either...