First ultrasound 😞

So I had my first ultrasound today. By my period I'm supposed to be 7 weeks 3 days. We were doing the ultrasound and there was a sack but no fetus. The sack measured 5 weeks and 5 days. So my midwife redid my hgc levels and ill get them back tomorrow. She said either we are off on our dates and I'm only 5 weeks 5 days and if so its normal not to see anything or I'm having a chemical pregnancy. I've been so sick this week nauseous and indigestion like crazy which she said is a good sign. If my levels are still going up then I'm getting another ultrasound Monday. Has this happened to anyone? What was the outcome? So stressed....