C.O.
if you have had sex - it's possible you are pregnant.
I'm not a doctor. I would think that you would need to get a blood test to find out for sure if you were pregnant...if the home test came out negative but you are still showing symptoms - go to the doctor for a blood test...
If you are really trying to get pregnant - you can talk yourself into any symptom.
If you want to know for sure - go to the doctor for a blood test.