Can Spotting During Pregnancy Forewarn Miscarriage?

i was 8 weeks pregnant ..having spotting type bleeding from day 1..and two days before i got bleeding like a period went to see doc and she scanned and said i m having a miscarriage,,and she askedd me to go home and let it happen naturaly..now i came home..first night i got bleeding accomapanied with cramps and bean sized clotts but i didnt get to see any sac..now the other morning i felt fine with lesser bleeding ,,than this night i did get cramps again and very few only three clots i guess.. i took a ponstan and slept..now since morning ..my bleeding flow and cramping is just like my 3rd day normal period one...what do u think i could have passed out the sac without noticing it?? should i go to doc for scan or still wait a day or two?? please answer asap will be very obliged...