I Had A Scan Again Today, Im Unsure How Many

i had a scan again today, im unsure how many weeks i am now, i found out about the pregnancy on the 4th of july, i had a tiny bit of brown blood on the 8th. Hgx going up but not doubling, i have 2 sacs 1 measuring 22mm and 1 16mm, my last scan she said she was sure there was a yolk sac, but this scan a diff sonographer said she couldnt? Both internal scans. im so worried ive lost my longed for dream, should i be worried? im 32 and this is my 1st pregnancy