have any of you had your due date taken away???

jessie

So I went for an ultrasound and according to lmp I'm 12w 2d but according to measurements I'm 13w 2d so they took away my due date until my next obgyn appointment August 1st... like I just want to know how much longer I have to wait to find out the sex will it be in the next 3 weeks or the next 4 weeks or will it be longer I'm growing impatient