Baby measuring 13 days behind

Jessica

I had my first u/s, According to my LMC (10/08) I should be 8W3D (very regular 28 day cycles) nurse said Baby was measuring 6W3D, I got my positive result 11/10.. heartbeat was 155 BPM.. I really don’t understand how I could only be 6 weeks pregnant.. i am a little nervous about this