No baby on ultrasound

I had my levels check at 4weeks my levels was 87. At 4w3d my levels was 714 but no pregnancy would show in an ultrasound so I had to come back in 2 days which was today 4w5d my hcg levels are 1800 but still no baby. They think I’m might be having a ectopic pregnancy so I have to go back in 2 more days to check my levels and see a specialist. I try to tell myself stay positive, it’s still early but I can’t help but feel sad. Has this ever happened to anyone before? What as the outcome?