Does this sound like a chemical pregnancy

I took a preg test on May 10 an it was negative then my bbt starting dropping so I figured my period would show up soon. it started a day later than usual on May 13 I bleed normally for 3 days with some more cramping than normal. I started opks on cycle day 10 (Friday may 22)like I normally do and the test came back blazing positive which was weird so I took a pregnancy test that came back fairly positive took 3 more and a digital that said pregnant. I been brown spotting on and off since friday and my test seem to be getting lighter i can't get into my ob till Thursday. Any of you ladies have a insight on to what may be happening? Feel like I lost my rainbow baby. If was a chemical how am I having postive test almost 2 weeks later