What Causes Pain In Lower Abdomen With Sore Breasts?

Hi, I have a question. I dont know what is going on, but lately i have been feeling really sick, and I have a feeling its because i could be pregnant. The last time I had a normal period was on November 15, and my boyfriend had came in me after the last day of my period. Which was on November 21. Ive been feeling some symptoms for the past 2 weeks. The odd the thing is, on Dec 6 I got my period. It only lasted 3 days, and it was normal bleeding, not light. I usually get my period around the middle of the month or the last week of the month. After my period, Ive been feeling really sick Id get up in the morning and feel really dizzy, even during the days id feel like puking or feel really dizzy and id get headaches. My lower abdomen would hurt but it would go away. sometime my breasts feel a little sore, but it would also go away, My appetite had change, Ive been eating alot that usual, and Usually I am never hungry, but when it comes to a point where i see food I automatically just eat it. Ive been also getting heartburn, and i dont know why. One morning around 2 weeks ago, I remember running out of my class and I puked in the morning. I felt really dizzy. I also get fevers. usually i would be freezing cold, my hands would be as cold as ice, but my forehead would be really warm. I have taken two pregnancy tests right after my 3 day bleeding, and it had proven negative. I still dont understand, why I am feeling like this..