It doesn't matter how many tests you take -- those tests report amounts of a hormone that you don't produce until the egg has implanted... and you usually don't make enough for it to show up on a test until around when your period is due. You're only 4 days after it was due... it's certainly possible that you're pregnant. A blood test can tell you for sure (see your OB-GYN). I had a friend who tested negative for about 2 weeks and then a blood test showed positive. So you absolutely could be pregnant. All that said, you could just be late. It happens!
at 9:02 PM on Dec. 16, 2009