My wife has a regular menstrual cycle of 25 days, her periods got delayed this month so we took a self pregnancy test on the 28th day using the kit. The first test showed a positive result however the second line was very light, so to double check the result we repeated the test on the 35th day, but this time the result came out negative, however she has not got her periods till now,What could be the reason for this? Should we undergo any other diagnosis for this? We had a positive pregnancy during August of 2018 but the foetus was aborted due to lack of heartbeat so we underwent D&C during October 2018. This is the second time. So kindly advise on the next course of action.