Unprotected sex all these years.. Infertile?

So, I've had one miscarriage a couple years ago.

I'm allergic to all birth control its terrible and latex on top of that.. So I've been having sex for about 7 years unprotected here and there but three years with a serious boyfriend without any birth control. No pregnancies except one but I miscarried at 6 weeks.

Is there a cause for concern? I haven't ever TTC but I have sex every day and I never get pregnant. Could I be infertile?

How do I check?