Sore nipples , fatigue, nausea, fullness in abdomen , late period lighter and shorter than normal. neg pregnancy test a week ago. pregnant?

Yes: You could be pregnant and the test has not had sufficient time in which to become positive. But many other things could be responsible for your symptoms. If they keep up and you are retested negatively, go see an ob/gyn.

QUESTIONS: When was the last period? Any ultrasound done? If not, should get one. Was the pregnancy test done in urine or blood? If urine, repeat the test with serum (blood).