** Thanks for contacting with your health concern 1. since there is a delay in periods with signs of premenstrual tension positive but home pregnancy test [HPT], is negative it could be due to certain lifestyle changes were done recently [if any] like: - excessive stress - loosing or putting too much of weight [present] - heavy exercises - suffering from PCOD [polycystic ovarian disease] or having a high level of prolactin [hormone] - Also, a diet low in fiber and high in saturated fats can cause irregular periods, likewise low thyroid [hypothyroidism] can also cause the same, so check with your Doctor. 2. It is best to seek suggestion to know why you have missed your periods, a Gynecologist would be ideal to consult, for appropriate examination/ investigations