Should Gestational Sac show by now?

My first day of my last period was Sept 12 and OPKs say I ovulated on October 2. I got a positive test this past Sunday and Tuesday. i got an ultrasound today (Oct 18) a little earlier than most would because I have history of an ectopic. No gestational sac was showing and I have a cyst on my left side 😭 Should the sac be showing by now, or is my ovulation a little late so it wouldn’t show yet? Kinda freaking that I have an ectopic again 😭😭😭 HALPPPP