As the ladies said it may be to early to see something. I would try it again when you are about seven weeks they should be able to see something then. Good luck
I am with hopeful, it may be too early. Wait a few weeks and get another u/s. You may also want to get your HCG checked again in a few days to see if it is still going up.
I dont know about the hormone count but you may not see a heartbeat at 5 weeks 6 days. Dont stress yet. Wait a week or so and get another ultra sound done. A few of us on here have seen, heard, or had this happen and the baby was just fine.