Amniotic sack coming through cervix, has anyone experienced this when getting checked?

I am 38w and 2d and I got checked today and I was at 2cm and 90% effaced. He also said that the amniotic sack was coming through my cervix. And he said it felt like a water balloon coming out of my cervix. Has anyone else experienced this? If so, what is this called/ did your water break soon after found/ is my water more likely to break now that it’s protruding through? My doctor thinks it shouldn’t be long and that if it does pop to come into L&D.