Went to the ER 10/29 at (6wks) i was told after having a regular than a vaginal ultrasound, that there was a sac but there was nothing inside. Cramps returned Friday 11/7 went to the ER again 11/9. They still didn't see anything but a sac measuring at 7w 2d, with the regular ultrasound, but told me to wait for another vaginal one. After only a few seconds they seen a baby about 8w 2d. No one has a clue why this baby didn't show up on the first ultrasound. My question is should i be worried about them only seeing one baby.