I've tried to become pregnant for two years got pregnant once had a miscarriage at 7 weeks do you think i'm infertile or any ideas why it won't happen?

Yes: 'infertility' is defined as unprotected intercourse without conception for one year. This is based on studies demonstrating 85-90% of normal couples conceive in that time. This definition does not depend at all on 'actively trying.' It's therefore 85% chance you and/or your husband have a fertility problem, you'd need a doctor's evaluation to say 'what' the problem is.