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I'm usually pretty regular. I was a week late on my period and took a pregnancy test. Came back negative. A week later still no period, i took another test. Came back negative. Yesterday, after three weeks with no period. I took another test. Came back positive! Early Today, I started passing large blood clots(all day) and the test came back as a negative. I believe I'm having a miscarriage but really confused with the inconsistency of the test results. Anyone else ever experience something like this? Or know what might have happened? and i've had bloating and discomfort for the last 3 weeks like I usually do on/around my period.