Yesterday I had an ultrasound at week 4 and they said it was a miscarr…

Yesterday I had an ultrasound at week 4 and they said it was a miscarriage, while another sonographer said it was 5 weeks but doesn't match my cycle. My period was July 24th and he said this pregnancy is September-ish, but August you had a problem ?‍♀️ I'm just really worried. I have a follow-up ultrasound in a week, anyone else experience something like this? After hearing about the miscarriage, I'm very worried. It hurts the umbilical cord, but not that much, as there's some discomfort in the belly area (