I have been having headaches nasuea lower back pains stomach cramps muscle spasms extreme fatigue my breasts hurt all the time and have changed colors and I am very bloated. I have had these symptoms for the last two months. I also had a spotty period last month (the blood was super dark, and there was not enough for me to need to use a tampon or pad). However, every pregnancy tests I have taken have come out negative. What else could cause these symptoms???