Very confused

In office pregnancy test was negative and ultrasound shows nothing but thickened uterine lining. First positive test was 3 weeks ago Sunday. Home test is clearly positive. No bleeding. Has anyone had anything similar where they miscarried and never actually bled and nothing ever showed in their uterus. I’ve had multiple positive urine tests and 2 positive blood tests (level 452 at 5 weeks so obviously low for that gestation but very positive nonetheless) the waiting to see what is happening is making me crazy.

This is today’s test, 6 hours after the “negative” test in office. I should be 6 weeks, obviously this is not going to be a healthy baby if we see nothing in the uterus but I don’t want to miss an ectopic. They said nothing in the tubes either though. So confused.