Am i pregnant so soon???

So on july 1st i miscarried and the bleeding stopped on the 5th. Completely gone. We had sex on the 8th and 10th and ovulated last week sometime. I woke up this morning with a bit of light pink blood. Now its gone. Been super nauseous the past 2 days. Just wondering if anyone went through this before and possibly could be pregnant so soon. I've never been pregnant except for the mc i just had. I got blood done Monday and hcg went from 27 to 13. I was told pregnancy tests don't read hcg unless its at least 25. Please help