Chemical Pregnancy?

I think I had a chemical pregnancy. I got what looked like positives on a blue dye and pink dye test. I tested again a few days later and got a BFN and then AF came a day after that. *TMI* The first day of AF I passed quite a large piece of tissue. I also had some odd cramping a week before AF which I thought were possibly cramps caused by implantation because I don't cramp before AF unless it's the day of. Just wondering what everyone thinks or if you've had a chemical pregnancy and are willing to share what your experience was. I have been a little upset, but not sure if that's what even happened. 😕