Symptoms disappeared?

So, weeks 6 and 7 were super rough for me. Nausea, starving all the time but couldn't stomach anything, so tired I was having to take 3 hour naps a day, etc. I hit 8 weeks on Wednesday, and have felt pretty great ever since. Has me feeling super scared maybe I've miscarried and don't know it? My first appointment and ultrasound are on Tuesday at 8+6, finally. So scared to get in there and not have a heartbeat. Aside from looking like a whale, I really don't feel pregnant anymore. 😕