has anyone else gotten such an early positive?

I started my period on September 15th 2013. 
​On October 2nd, I woke up with some spotting & immediately knew it shouldn't be my period so I bought a dollar store pregnancy test that came back positive!!!! took over eight more tests all positive. I just knew something was wrong bc who gets a positive on CD 17!?!? when I went to the doctor two days later on the 4th my HCG levels were a 32, they told me then I was miscarrying. We are currently trying again.
​have any of you ever gotten a positive that early? I thought it was impossible. Could something be wrong with me that caused the early positive & miscarriage? the doctor I went to just kind of looked at me strange.