Hey hunny. I did IVF as well. 5+3 today. I have my first scan booked for Monday at 5+5. Doctor says that it definitely may be too early to see anything and not to freak out if they can't find the pregnancy. (IVF babies can often take a couple extra days to show up because they often implant later than au naturale babies.) My hCG has doubled correctly over the last couple weeks, but I implanted late and am not even going to get to hCG 1000 until Sunday. (5+4) Some sacs won't show up on u/s until hCG is at 2000+, so doctor said she'll bring me back in at 6+2 if we don't see anything 5+5. Also, remember you've got a lot of lining in your uterus and the sac is so tiny right now. Sometimes things just don't show up on some u/s machines- they all have different sensitivities.
Keeping you in my thoughts, hun.
I hope Monday's u/s goes a little more smoothly and you get to see your bean!