Possible miscarriage coming...

So today I went to Dr. Supposed to be 7w3d according to my LMP. We were expecting to hear the heartbeat. Tech said she saw it but was to faint to pick up. On to see the Dr.. he tells us that baby is only measuring about 5 1/2 weeks. Says I may end up with miscarriage. I don't know what to think at this point. I'm supposed to go back in a week to 'see if there is any improvement'. I'm a hot mess. Hubby is trying to comfort me, but I can tell he's just holding it all in. Does any of this sound familiar to anyone??