Not at all, dates can be off by 1-2 weeks. Depends on the time of ovulation and implantation. Between Ovulation and Implantation, anywhere between 3 to 10 days is possible!!
Normal... I thought I was 7 weeks pregnant but after ultra sound Dr said I was only 5W and a few days. It was determined that I was less due to my cycles. Normal is 28 day cycle but mine are 35 days apart.