I Suspect I Am Pregnant. Two Tests Have Read Negative,

I suspect I am pregnant. Two tests have read negative, I have not missed a period, yet the symptoms won't go away. For the past month I've been bloated, have feelings of stretching around my navel, pain in my back and pelvis and my breasts have increased in size. I have not had a 'worm out' in a while and was wondering if it was safe?