7w Mild nausea but not sick

Erin • Early MC Oct `14, Missed MC April `15 & Sept ‘18 💔
I'm 7w1d and have waves of nausea regularly but usually not bad and have yet to be sick.  Sore breasts and exhausted, and sometimes back pain (I'm a server so I stand/walk a lot)
Just keep hearing that if you're vomiting there's more of a chance the pregnancy is a viable one than if you're not vomiting.  
I need reassurance baby is ok and here to stay!
I was sick 1x with my first pregnancy that ended in early mc in October so I know vomiting isn't a guarantee but I feel like I should be by now!
1st ultrasound is next Friday.  I feel like I'll be in edge until I see something on the screen