Sad Update 9 weeks

I've been posting each week after my ultrasounds. Yes I have had one each week since my first appointment at 6 weeks because they have all been concerning. My first was a concern because the heartbeat was in the 90's. My next 2 were scary because there was no growth each week and same low heartbeat. Today was the worst news. The baby is still measuring at 6 weeks even though tomorrow I will be 9 weeks and the heartbeat went down into the 60's. This is my first and I'm so scared of what's to come next. Anyone with a similar experience that can give me some advice would be great. 

Thanks for reading.