Hi, and thanks for your medical question on eHealth forum!
If you had a pregnancy test in December and it was positive, then you could be pregnant or it could be false positive test. Even if you are pregnant, it does not mean you will have the classical symptoms of pregnancy for sure. Some smooth sail with no symptoms.
What is important is that you must consult a gynecologist, undergo a scan at 8 weeks and some tests to know that the baby is fine. Hope this helps. Take care!