I'm so confused am I pregnant

So I had positive pregnancy tests and been the hospital for hcg bloods 11 days ago, the bloods have doubled every 48 hours but when they scanned me there was nothing and put it down to being too early... Also when I was at the hospital they done a test and it was very faint but they've messaged my doctor saying its negative but I've got a scan tomorrow because of my rising hcg levels. I'm so confused? Someone comment