AF due today still BFN

I'm at a loss. I took my first round of Clomid this month and nothing. We've been at this for a year and a half. Nothing seems to be wrong with my husband and I but it just isn't happening. I'm defeated today. I felt like this was it. But, still a BFN. Has anyone ever gotten a BFP after her missed period. I just feel like it would have picked up by now. Ugh. This process is confusing and hurtful.