I Have Had A Period That Last One Day. I Am Having Other Symptoms Like Nausea, Low Back Pain, Headaches, Occasional Abdominal Pain, And Fatigue. What Could Be The Cause? I Had A Negative Home Pregnancy Test.

I tested negative with home and doctor testing for my whole first trimester then finally in my fourth month I tested positive. There is a possibility that you could be pregnant. See if you continue with the symptoms and keep taking pregnancy tests.
Also, it could be a flu bug causing your period to re-act differently. Good luck and praise the Lord if you are pregnant or praise the Lord if you aren't pregnant:).

I think you experienced spotting that is an early sign of pregnancy and also you have many other symptoms. Home pregnancy test often comes negative because of poor timings and poor sample. I mean you need the sample of urine when you come up from your bed in the morning. This urine has more probability to give the accurate results. Secondly you can take blood pregnancy test which are more accurate than urine tests.

Be in touch with your doctor and take the pregnancy test as early as possible.