Hi Doctor. Im Missed Period On 1st June. I Did

Hi doctor. Im missed period on 1st june. I did my scan n urune test on 13 july. The result from urine test is positive but in scan nothing can be seen. The doc gv me appoinment on august 11. Now i hv slightly vagina bleeding. I went to gynae and he did vagina scan. Doc said im supposed 9 week but the scan showed 4 week sac. He gv me duphaston and ask me come after week. Im really worried about late conception or baby not growth well. So doc pls me to explain