Sayang, bleeding in early pregnancy tu memang boleh happen tapi tak boleh main-main, you need to see your doctor or go to the hospital sekarang juga to check kalau baby okay, especially since scan shows 4 weeks tapi you're at 6 weeks by dates. Better safe than sorry lah! A few of my mum friends also had spotting early on but doctor visit je yang buat hati tenang, so jangan delay ya