Very discouraged

My fiancé and I have been trying for a year and half now, my periods are irregular. I got on birth-control got off and trying again now. I have quite a few symptoms such as breast tenderness sometimes nauseous, not liking food I love. I took a HPT 2 days ago (first morning pee) got a BFN! I'm starting to feel like it's never going to happen. I really want this for us.