possible pregnancy after miscarriage? help?

abigail
Hey guys this is my first post on here, unfortunately I had a miscarriage almost 4 weeks ago. 
And I'm still getting quite strong positive pregnancy tests, I was advised to go back to the early pregnancy unit and they scanned me. 
They said there is something there but it doesn't look like "old pregnancy tissue" :/ 
I asked if it could be a new pregnancy and they sent me to get some bloods done. I get the results back later but they told me it could still be inconclusive. 
I'm really confused and we're hoping this could be a new pregnancy but I don't want to get my hopes up. 
Has anyone got any advise on this?
I'm very anxious about calling them later for the results m. But knowing me it will still be inconclusive! If it is then I have to go back in a week for another scan.