according to your findings the possibilities are,
-molar pregnancy: with irregular sac and products of conception seen as small grape like vesicles and elevated hcg
-blighted ovum: in it also fetal pole
will not be seen but hcg levels will not be that much high,
so you confirm with your doctor as early as possible,
and in case of molar pregnancy go for suction and evacuation as early as possible,
in case of blighted ovum D&C is adviced.