i had a scan at just over 4 weeks and they could barely see anything at all, just a 3mm splodge that 'may or may not be a baby's sac', heh, so don't worry about the scan. i'm so glad you insisted on blood tests. i guess the only thing to do is just wait, i know how hard that is though. you could always call them earlier to see if the results have come back yet? i always nagged when i was waiting for mine, and often got them earlier than i was told they'd be ready.