Lost my virginity 3wks ago used a condom but having some pregnancy symptoms such as slight headaches, discharge (more than normal) mood swings I'm 16?

Not Pregnant. I believe this question has already been answered. One cannot get pregnant without sperm. It is impossible. You are not in any way describing anything that would be specifically pregnancy symptoms. You are not pregnant. But, since you doubt that a physician would speak the truth to that, if your period has not arrived then please do a pregnancy test. If your period arrived that is further proof.