This may sound strange

This is may be kind of a strange question but I thought this would be the best place to ask. So my boyfriend and I have been having unprotected sex for 6 months now and I have not gotten pregnant. We arnt trying to get pregnant but I'm a little worried since we have sex almost everyday and I havnt gotten pregnant. I'm worried that I may have fertility issues and we have talked about having kids so I'm scared we may not be able to. I know he can have kids cause he already has 2 girls. Is this something I should be worried about?