Uterian Bloating/Stretching?

I have been trying to get pregnant with our second child. I have unexplained secondary infertility. I dont get my period on my own without the Provera. On Saturday I had a little bit of spotting I wiped once and it went away, then the next time i went to the bathroom it was gone. And Since then I feel like I have been having Symptoms of early pregnancy. On Saturday and Sunday I feel like my breasts were throbing. My mouth was salvating, and I was just feeling really weird. Now today its seems liek those symptoms have gone away. I have the occasional breast tenderness and pain, more like a tingely feeling. And right now the only symptoms i am having is your can clearly see the viens in my chest( I have never noticed them before)I am having a very hard time staying asleep at night. And for the past couple of days I have been having slight cramps, but mostly i feels like a bloaty/stretchy feeling in my lower abdomen. I dont know if I ovulated this month or not, and I took a pregnancy test on Sunday and it was negative. The ony thing that concerns me is that i feel like my uterus is a ballon and getting bigger. Should I be Concerned? Has anyone else ever had these symptoms and then ended up having a postive pregnancy test? A Doctors hel pwould be great!!! Thank you so much!