Scan related

Just need some answers if possible 😟 im pregnant according to me i know im 13weeks but i went for my scan last week but they couldnt find nothing with the ultra scan so had to do the internal scan after they done that they couldnt find no heart beat so told me to go wednesday agen for rescan so inwas wondering if it a possible to find heart beat on Wednesday or do i have to accept its a possible miscarriage 😞😞 was really upset on the scan and now so not looking forward to wednesday feeling scared x