I think I may be pregnant. If I were thinking on schedule, I should have started my period four days ago now, and I did miss the previous period as well. My last cycle started on July 9th. I have taken about six or seven home pregnancy tests, and they all say negative. My friend suggested it could be an ovarian cyst, however. My breasts have grown almost 1.5 sizes; my abdomen is much larger and prominant; my emotions are all over the place; I am more tired than usual; I am much warmer than usual; I do get nauseous often, but have not vomited; my cycles are either 27 or 28 days long, my period always lasts four days with very light bleeding on the last day. I did have spotting two days in a row about three weeks ago, but nothing more. What is your advice, what can I do?