Morning sickness & miscarriage

Aurora

I have had my 7week scan earlier this week and it showed twin sacs that were completely empty.... I'm devastated... . But I still have some morning sickness and my Hcg levels are rising (28000 at 6weeks and 72000 at 7 weeks).  Is this just a cruel tease or could we still have a chance of a baby?  Is it normal to have morning sickness right up until you miscarry or should it have eased/stopped as an indicator that miscarriage is imminent...

Help!