7wk ultrasound but only measuring 5wks

I'm not sure if I should post this here but I went in for an ultrasound today but only measured 5wks. According to my lmp I should be 7wks. My doctor saw the gestational sac but nothing else and it's a little unnerving due to having a miscarriage in Oct of last year. Blood was drawn and I go back next week (valentine's day) to see if things are progressing as they should. I need some sort of light on this situation because right now I don't have a good feeling about this. Hubby (who can't keep his mouth shut) has told almost everyone he knows I'm pregnant and he did so with the one I miscarried and I'm having some resentment even telling him that I'm pregnant! So confused.