Only the gestation sac

I’m suppose to be 6 weeks and 2 days and I’m so scared I had an ultrasound around 11am on the 28th well they didn’t find anything only my gestation sac it wasn’t fully developed no yolk sac my doctor thinks I’m very very early and so we did a blood test hopefully my levels are still rising as they should and nothing is wrong this is my first pregnancy. I’m just so scared what they will tell me next week at my appointment 😭. Wish me luck if anyone has gone through this before please let me know if I should be considered or if I should just forget about it like my doctor said because it might be too early.