Empty sac at 5 weeks and 5 days

Bernice
My first ultrasound done thru my tummy and vaginal then told me, they see nothing but a sac.. i had little stabbing pains in different parts of my stomach.i have no abdominal pain and or bleeding.. im told ill have another ultrasound in a week.. a bit scared.. anoxious and very worried.. Not sure if im pregnant or not..