On the 14th of april i had a 3 day period when my regular cycle is 5 days. Since then my boyfriend and I have had unprotected sex many times. It is now the 23rd of march and I have not yet had my period for this month. For the past couple of weeks i have been very tired, my breasts have been tender and my boyfriend says they look bigger, my areola is a little bit darker than normal and you can see the veins in my breasts now, I get upset at just about everything I cry get mad and frustrate easily, and i have been having cramps, headaches every now and then, my back sometimes hurts if i am up too long. I have gained some weight and quickly but I think it is because of me eating a lot. Acouple weeks ago i was in the ER and they did an ultra sound and found a small cyst on my ovary and also told me that my uterine walls were thick so i should get my period but i never did. Is all of this happening because of the cyst or is there a possibility that i am pregnant.