mild cramping.....pms or implant cramping

I'm 14dpo and having mild cramping. I noticed a very very small amount of pink blood 12dpo. Ever since I have been mildly crampy. Took a test yesterday and today. Both negative. I've had nausea, fatigue, mood swings, and high cervical position. Had my peak on day 14 using femara. Just wondering if anyone else has had this and ended up pregnant? My predictor said to take a test on 3/9/17. I'm usually 28 day cycle. Today is 28. Am I just testing too soon?