4 weeks Delayed But Negative PT

Hi, I'm 4 weeks Delayed after my last missed period but still negative pregnancy test. My last period is Dec 5, 2019. Then I have no sign of menstruation at January 5 to 8, 2020 until I'm so excited to take a first pregnancy test on January 30, 2020 and it was negative so I went to my doctor. And my doctor told me that I have to go for an ultrasound the result is negative. No sign of pcos and she was found out in the ultrasound results that I'm so fertile. She prescribed me Vit E and Conzase also for my husband and my doc said we have to contact with my husband that day January 30,2020. Then until now February . 9, 2020 still negative pregnancy test. Pls help me know the answer am I pregnant or not? ?