hey guys, so my period due the 31. I ovulated on the 16th and 17th. I woke up this morning dry heaving. and yesterday I had little cramps but not like period cramps. anyways I took a test this morning first response it said negative. so my question is the box days 3 to 2 days before af due 99 percent accurate. so does this mean I'm not pregnant then? or what? today would be 11 days past ovulation.