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i have been having stomach pain off and on for close to a month and i have not had my period yet i am close to 3 weeks late.i went throught this kind of pain with my first child. but i have taking 7 pregnancy test and they all have been negative i went to my doctor a i went to my doctors and had a test done and it was negative she said it was my birth control but i had stopped using it over a month ago. and i have been cramping very badly that i cry and can't sleep and i wanted someones help on this subject on what they think it is. should i buy another pregnancy test just to be sure? please help me