I have taken 4 pregnancy test within the last month and they all come back negative but ive been experiencing nausa, headaches, cramps, fatigue, dizziness, and certain smells just send me running to the bathroom. I have irregualr periods so im not sure when to expect my period. I havent been under any stress other than the normal day to day. ive also have went to the doctor and the test come up the same. Is there still a chance that I may be?