Gestational sac but no yolk sac

Hey everyone.

Just out of curiosity, I went to the ER the other night due to some bleeding, which was after sex and this being my first pregnancy after trying for 4 years I was a little nervous..

I thought I was about 7 weeks according to my lmp, they measured at 5 weeks 6 days.

HCG Quantitative was 3578.0.. they honestly didnt tell me much, rather than they seen the gestational sac and tissue inside, but they didnt say anything about the yolk sac so I was just curious on your experiences, any information would help considering this is my first. The ER told me to call my obgyn on monday , just to go over results and go from there, but I figured I would ask you ladies. Thank you so much for the help!