??!!??

Last period was November 23rd. I was supposed to started again December 27th and 2 days before the 27th I took a pregnancy test and it came out negative. It’s January 7th and I still haven’t gotten my period. Ive been nauseous. Sore breast. Cramping in my lower stomach and a huge appetite. I always feel like I have to pass out and I always got the urge to pee. What should I do?! Or what could it be !?