This is the second day this has happened, today was far more painful. At night time the pain felt like it was coming from my back and than moved it's way to my lower stomach. I've never felt pain like this and I've had very bad menstrual cramps before; even to the point of fainting and vomiting. The pain came and went however, it gets so bad that i feel a tightness in my abdomen and especially in my throat and i can't breath properly. A part of me thinks i may be pregnant but i have to wait till next week for my period. Could this pain be from me being pregnant, if i were i would only be 2 weeks or could this simply be menstrual cramps or anything else please help me.