I have taken 6 boxes , half 7-11 brand and half cvs brand of these tests , 12 tests in total , all came back positive .... but first response and clear blue all come back negative , I had a little spotting around when my period was due ... but nothing else and not I’m 5 days passed my missed period , and this is all I’m getting , some of the tests are a little older hence the darker yellow color , but all were positive right away and blue in color deff not evap , what gives ???