Twin feeling

Has anyone had a very strong feeling you were having twins? I'm 10 weeks currently. My 6 weeks scan had possibly 2 sacs then 8 weeks had a small sac with one baby but me and my husband can't shake the feeling of there being 2 babies. My obgyn does very quick ultrasounds and said no you would clearly see them already and shakes it off knowing twins run in both our familys...im going in at 12 weeks should I know for sure then?