First baby

So I'm so worried and I'm trying not to be, I'm 6w3ds and my first ultrasound is next Tuesday, I had to tell my boss that I'm pregnant and since that day it's just been stressful with her because I can't do a couple of things that she asks me to, do to the fact that I work in the dental field and the nitrous gas can cause a problem with the baby or miscarriage, and there is some radiation that I don't want to take the chance on getting around so I started working up from, now she is asking me to take 50lbs boxes upstairs and gets upset at me when I have someone else do it, I just want everything to be ok. And I don't want to take the chance on anything at all happening! Does anybody have tips on how to get stress released in a healthyway?