Pregnancy after chemical?

So I misscarried around January 22 and bled till about the first of February or maybe I bit later. On February 15 I had my blood levels drawn for the last time and they said they were back down to zero. It had been 2 weeks since they had last been drawn and before they measured around 59 if I am correct. A week after I got my blood drawn I took a pregnancy test and showed me a positive and still getting positives to this day. My question is how far along could I be? Is there a way to figure this out or just a doctor visit?