Will I be able to?

Okay ladies help me out. Me and my boyfriend have been together for a year. We have had sex MANY times and as CRAZY as it sounds we don't use protection. Most of the time he pulls out and depending where I am at in my fertile days sometimes I let him cum in me. Okay so here's the crazy part I've never ended up pregnant. And we've done it a lot. Now don't think different THANK GOD I haven't we don't need a baby. But I am soooo scared that when we do get married and want to have kids we won't be able to. :( can anyone give me advice or anything?