High anxiety about ultra sound

I had a miscarriage in May after 2 years of trying for a baby, we just found out that I’m pregnant again (which is a miracle) and I go in to have a trans vaginal ultra sound in two weeks. I feel like they’re going to tell me I’m having an ectopic or something bad. I just feel this is too good to be true. I’m trying so hard to stay positive, I just have my moments and had to vent. I’ve been having back pain and cramping on and off. I also had a small twinge in my shoulder for 5 seconds the other day and I’ve worried myself sick. I know worrying isn’t good either. I’m trying to stay busy and healthy... any advice or encouragement is appreciated!