Hang in there honey, it is early.
The quality of the u/s machine has something to do with it too. When they did an u/s on the crappy dr office one the first OB couldn't find anything. It took an old pro to find the sac. A few days later I had a scheduled u/s with a good machine, different story. We could see much better and both u/s were internal.
I'll keep hoping that is the case for you.
Keep us posted, I'll be thinking good things for you.