Hi, a few weeks ago I started my period but it wasn't right. It lasted maybe two or three days and not the regular length that it always does. This has never happened before and my period is irregular meaning I never know when I am going to start. I have been tired a lot here lately, eating like crazy, and getting a little bit bigger. I have two kids already and both pregnancies were different. The first I knew I was pregnant because of the soreness all over and the second I didn't even know until I went to be put on birth control. So how do I know for sure if I really am or not if my tests keep coming back as negative. I have taken four and all the same thing. My sister in law had taken two once and they were both negative and then about a week later she had a miscarriage. Can you please help. I don't understand it.

Having irregular cycles makes it more difficult to know since you can't always count on a period not showing up as a sign. If you at least have one each month, just not always starting about the same time, see what happens next month when you suspect your period might be due. You could also check with your doctor, explain the unusual period you last had and see if they will do a blood test for pregnancy.