i am nearly 5 wks pregnant 4wks and 4days, i had to go to a e yesterday due to pain i was having, this was checked via scan and everything was ok. as the pregnancy was due to ivf they think the pain is due to pessaries iam taking which i doubled, as told to. on the scan they saw 2 sacs one was size 5.mm and had an visable embryo in and the other was emtpty sac but measured 5.5mm do u think iam expecting twins? i had 2 embryos inserted. why would 1 contain an embryo?and the other not is it too early? why was second sac bigger ?