chemical pregnancy

I believe I have experienced a chemical pregnancy because I was 4 days late and I have belly ache so bad it felt like I had food poisoning but I didn't had it a few times before I knew I missed my period then when the fourth day cane of my missed period I started bleeding heavier the normal with a lot of clots is this a chemical? Maybe the egg didn't stick proberly and that's why I was late I felt like I saw a faint line on the first response