Confused

I went for an early OB check up on Sept 11 thinking i was 8w since my last period was July 12 and i was told I was measuring 6w1d measuring 4.3 mm they did vaginal and abdominal ultrasound they did find an intrauterine gestational sac with a “mild debris” of 39.5mm but no heart beat they said it could have been too soon but im so confused my appointment is October 6th.. I have not had much symptoms anymore. No bloating. Or any of that, i used to track my period so I know when my periods would come and go .. is there anyone who has had the same problem? But had a good outcome ? I’m full of anxiety . I haven’t had any bleeding or pains .. and hopefully I don’t .. according to my app I should be 10w4d

but than another says 8w. so I’m confused as heck.