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Melissa

So I took a blue dye pregnancy test 3 days ago right away in the morning and it came back positive. The next morning I took another blue dye test right away in the morning and it came back positive. Today, I took a red dye after supper but it came back negative. My period is in 2 days so I know it is still a little early but how common is it to get two positives from blue dye in the morning and then a negative from a red dye in the afternoon....