Getting pregnant

My partner and I have been having unprotected sex a almost 6 months now, we weren't specifically trying to have a baby to start with but we've now both agreed that we'd like for it to happen sometime soon and are actively trying. I stopped topping my jab up a few months before and we just used condoms until we went off contraceptives all together. We have sex almost every day but I'm still failing to fall pregnant, my periods come on time every month, is there something wrong with me?