My wife got her periods on 1th of september and on 20th sept. We had unprotected sex. But today (8th october), is 38th day of her last periods and her periods has not come yet. We did a home pregnancy test four time in four days and the results were negative.,. But there comes out brown blood clot with urine for three times yesterday and today. Now she felt back and abdominal pain. Is it a sign of pregnancy? Or is it a sign of her periods? Or is she pregnant? Please guide.