Measuring ahead?

Michelle
My last period was August 7-12th. I found out I was pregnant August 28th due to morning sickness. I had my first appt on the 19th of this month, I should've been 10w4d but Tge baby measured 11w2d. My due date should've been may 12th. What would my due date be now? And is it normal to measure ahead? Second pregnancy.