Two vvvfl positives and then a negative

Katelyn

I have been testing for three days. On Wednesday I got my first vvvvvvfl with my fmu on an off brand blue dye test. Second test same thing. Third test this morning fmu, first response test- negative. Period should be due tomorrow if on a normally 28 day cycle. My periods never regular and I know my ovulation isn’t always when I think (two previous pregnancies). Any ideas?