Late period pregnancy success stories?

I am currently 8 days late for my period, I have taken a few tests already (including one this morning), but they have all been negative. I very rarely go late and the latest I have even been is 3 days, I have been feeling extremely irritable, I'm always tired, and been feeling slightly nauseous the past week. Has anyone else had a similar experience and ended up pregnant? I'm really hoping I am and feeling a little discouraged. Any advice is appreciated.