Has anyone had a small gestational sac in their first trimester that ended up catching up in the second trimester? Baby is measuring on track, but the gestational sac is measuring 6 days behind. Baby’s heart rate is over 150 at 7w1d. Worried about the baby running out of room, but everything I’ve read (and what my dr says) there’s an 80% chance it will end in miscarriage. Looking for hope or similar stories.