12 days late...

My husband and I are ttc- I am twelve days late which never happens. I'm also nauseous, sore boobs, headaches, and tired. These aren't normal symptoms for me with an upcoming menstrual cycle. I've taken two pregnancy tests and they are both negative. Has anyone else had this happen to them? I've emailed my doctor and waiting to hear back about what this could mean. Any information would help!