Gosh, hard to say. Was your period ever late or is this really early on? Women since the beginning of time have had what is called chemical pregnancies. They never had any confirmed pregnancy test and weren't 'really' pregnant as within a week or two of implantation, they miscarried. It is like it never got off the ground. If there was a fetus big enough to see, you'd have likely gotten a positive test. But you never know and you may never know. Your doctor could do an hcg test which would be more sensitive and pick up if ANY hormone is present that indicates pregnancy? You might try that so you know. Are you trying to get pregnant?