vaginapagina | Positive Pregnancy Test After Miscarriage? (Reply)

I started to miscarry on the 14th of June at five weeks three days pregnant, at that time my HGC levels were 40 and two days later when they were tested again they were at 10. I was told that things would progress naturally and I didn't need a further check up, I stopped bleeding five days later. A week later I took a pregnancy test in the middle of the day just to see if it would come back with anything and it was negative. On the 22nd I had unprotected sex with my partner and first thing this morning I took a pregnancy test and it came back positive, two more pregnancy tests taken later in the day came back negative.
Now, on to my question. Is it at all possible that I'm showing positive on a pregnancy test ten days after having sex because I'm pregnant or is it because of left over hormones in my system from the miscarriage? I can't seem to find any useful information online and my Dr can't see me until the 7th. What confuses me is the tests I have only detect as low as 25 HGC and my levels were 10 last I was tested, though I suppose it could just be more concentrated with early morning urine? Thank you in advance for any light you folks can shed on this.

(Cross posted to Pregnant)
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