Early pregnancy

Hi mummy, I have been experience light spotting on off since I got to know i'm pregnant and still does have it on daily basis. I'm not sure if baby gonna grow well ornot sigh I'm still in my early stage and I have previous miscarriages ): My HCG double up but it was in lower range below 100 so I had V scan but gynae couldn't see anything. My next appt will be next week, can't wait to know the outcome. Does anyone know if by next week I should be able to see a sac and fetus? does anyone goes thru spotting but have a healthy pregnancy?