I had an early us at 5+1 and all they saw was a very small sac and yolk sac. No fetal pole. Us tech said not to worry because most of the fetal poles don't show til 6 weeks. At our 10 week us we saw a healthy baby. I'm now 15+3 and growing
4 weeks is very soon. I honestly think you are ok! Have them check in a week or two!
Thank my Motorola Electrify for any random words.
Ashley,wife to ChrisMama to Madison
(7)Wyatt(3) and Natalie born June 18th 2013!
and our little bean who's back with God