I've been Iregular since I was 17, my period last about 3 days then I don't have my menstrual for about 3 months. I have it on and off. Since June of last year I started my period as regular as I ever had it. By husband and I have been sexually active with no protection. December 2nd was my last period. I have felt kinda nauseous but that was once near christmas. Could I be pregnant or am I starting to get irregular again.