Scared of twins?

Hey girls I have a family of 2 sets of twins so I am sorta scared to have twins lol! I know you can’t see another sac but I am so nervous for my next ultrasound to see if I am having twins! My hcg is higher than normal too so 😬 anyone have a family history of twins? Anyone have an early ultrasound and not see two sacs then go back 2 weeks later and see two? Y’all I am a nervous WRECK! 😂