Pregnancy spotting

Been spotting red, brown and pink for 6 days now. Had an ultrasound 4 days ago and was measuring a little early at 6w1d(only 2 days off) Dr said everything that should be in order is There it's just early and the fetal pole was Not developed yet so no heartbeat was detected. I have a scan a week from my last one( this Thursday) and of nothing has changed she mentioned talking about possibly a miscarriage. My cramps arnt awful and usually I don't spot all day until night time. Just so worried and wondering if anyone has ever gone through this. This will be baby #3