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Hi I was 16 days late for my period. Day 14 of the 16 days I took a pregnancy test and the results came negative. Day 17 I woke up to bleeding which was light pink in coloring and not heavy. Day 18 I’m heavier with a lot of cramping. My question is what could’ve caused this should I seek medical attention or just monitor everything. Should I take another pregnancy test is that possibility still exist?