text: my period has not come on, i'm spotting, both urine & blood test say i'm not pregnant. what is the problem?   there are lots of reasons to miss a period, not just pregnancy.  have you lost or gained a lot of weight?  have you been sick?  have you been under a lot of stress?  has your diet changed radically?  have you gone on or off the pill?  have you started or stopped any other medications?  there are lots of medical reasons to miss periods: utis, pid, stds, cancer, hormonal imbalances....  i would chill for this month.  if your period is not back to normal next month, i would see your doctor.