I would take a pregnancy test in the early morning, you will get the best results, however if you are not having a period it may be something else. You should probably schedule an appointment with your ObGyn to make sure. I got a positive test result when I was 3 weeks pregnant with my first child, 5 weeks with my second then with my 3rd (which I miscarried) they did bloodwork and I did about 12 home tests all negative and found out I was actually 8 weeks pregnant already before it showed positive!