Did anyone get a negative and a positive later?

Today I was suppose to start my period and no signs. Having very mild cramps that come and go and my boobs hurt SO bad. This is absolute worse they ever felt... I took a test when I got home and negative. I swear I saw it flash pink and then GONE... But I was drinking a lot of water at work so I'm wondering if it was diluted. I'm driving myself crazy here!!! So the question is did anyone get a positive after a negative? Or a positive days after missed period?