Early pregnancy advice needed

So I went to the ER with what I thought was a pulled chest muscle and came out with the news that I was pregnant. Blood test confirmed. The doctor I spoke with at the emergency room said congratulations but then let me know it was very early. Maybe a week or so. She also said most pregnancies they find that early "don't come to fruition". That was 2 days ago, but what that doctor said really worried me. I ended up buying the First Response triple check box which has the early detection test, the rapid results test and a digital test. I took the early detection one this morning and :

so still pregnant.... I'm planning on taking the next test tomorrow just to see if the line is getting darker.. and I'll save the digital for a few days but I was wondering when can I stop worrying about losing this? I had an early miscarriage in September 2017 and it really hurt both me and my husband. He's felt guilty all these months cuz he thought it was his fault for some rough sex.... I feel so sad that he's feeling like he can't be excited because he's scared we'll lose this one...

Also is this app generally accurate with weeks? The nurse said my hcg levels were about what I would see at 1 week or so but Glow is predicting about 4 weeks....?