Sayang, first time pregnant memang banyak soalan kan! At 8 weeks, it's actually quite normal to see just the gestational sac on the scan, setiap baby develop at their own pace. But honestly, you should ask your doctor directly lah to confirm everything is progressing well, sebab dia yang tau your full picture. Don't worry too much, a few of my mum friends went through the same thing and their babies turned out perfectly fine!