What Causes Delayed Menstruation Along With Clear Vaginal Discharge?

Hello, my wife has taken 7 pregnancy test all saying false. She has had a uti, and possible yeast infection that she took medicine to cure it. She is about 6 days late on her period and she also has missed a month way back when she was younger and.wasn't sexually active. She is now having discharge that is clear with blood. What could be going on. We are concerned. Thank you in advance.