I had unprotected sex about about 4 months ago. Ever since then my periods have been late, lighter then usual, and only 3 days long. I was getting a period ever month though up until September. I havent got a period since. I took two tests the first was negative. I took the other one two days ago and the second line was white instead of colored. I dont know if that makes any since. I have been easily irritated lately. I have also experienced what seems to be gas. I have one child already and what Im experiencing is the fluttering feeling you get when you are pregnant. I dont know what to think though. I have had a change in my diet and I also have had some stress in my life right now. Do you think it could be that?