no baby on u/s at 11 weeks

So, I had an ultrasound done at 9wk6d and at 11 wks, both times no baby was found. They could only see gestational and yolk sac. So at this point, I'm going with there's no baby and it's a blighted ovum (from research I've done). I'll be 12wks in 2 days and still haven't had any bleeding or cramping or anything. Still gaining weight, still getting bfp and still having pregnancy symptoms (sore & growing boobs, cravings, same symptoms I had my 1st pregnancy). Just curious how long it takes to pass this naturally or if I'll need a D&C? I just want it to be over so we can start trying again.