5 days late...BFN.

lisa
So, I'm 5 days late, and decided to test first thing this morning - only to be disappointed by a BFN. I'm never late, so this is new to me.. But any other reasons I don't have AF yet? Is it possible I'm testing too early?  We've only been trying for 3 months so I feel like I'm 'new' to all of this.