Should I be concerned? Losing symptoms

So I’m about 8 weeks along. I had a sono about 4 days ago and everything looked perfect and we could see a healthy heartbeat. I had a missed miscarriage last year around 8 weeks. I remember last time my symptoms disappeared and I thought nothing of it like “man I’m so glad I’m not nauseous anymore”… just 3 days ago my constant nausea has disappeared completely, my boobs which were really sore have quit aching, I’m still exhausted but those main symptoms just vanished and I’m so scared it may be the same thing. But seeing as I just saw baby, I don’t know if I even should be concerned.