Pregnancy symptoms 1 week after period

I still feel the pregnancy symptoms and its been a week after my preriod. What could this mean? Throwing up everyday, feeling nauseous ALL DAY, severe back pain, very tired, bad headaches, lower abdomen cramp, no sore breast (the only symptom i donf have). Can anyone tell me whats wrong? I know i am not pregnant because i tested 3 days after my missed period & it was negative and then AF showed up.!