TTC confusion

So I’m confused. I took a hpt and got a faint positive. Then I heard that breast milk can be used to test so I did and got 2 darker bfp. The thing is I’ve never been pregnant (as far as I know) and I’m producing colostrum or breast milk (not sure which one). Anyways I got a blood test done and it was negative. Doctor said I must have had an early miscarriage since I’m only 3 weeks. I was heart broken but then I took another test both ways and they said positive same as before. Urine was very light and bm or colostrum was pretty dark. Anyone ever been through something like this or have any idea of what’s going on?