7 weeks and symptoms just gone

I’m 7w2d pregnant and I started having morning sickness around 6 weeks then at 7 weeks it went away for the most part. I’m still having sore boobs at times and tired a lot of the time. But my back is hurting. No bleeding. I had a missed miscarriage at 12w4d 2 years ago so I’m just super nervous and paranoid and with my daughter my sickness never went away so this is different for me. Is it normal for my sickness to just leave this soon or is something wrong? I go for my first ultrasound on Monday at 7w6d so I’m trying to just wait it out and stay calm... I had my HGC checked at 4 weeks and 5 weeks and it was rising as it should. My test are still positive but I know if something were to happen it would take awhile for them to show negative. Anyone else experienced this?