Chemical pregnancy

Hey, so I’m pretty sure I’m having a chemical pregnancy, took my first test at 13dpo and was a faint line, took another 14 DPO and another faint line, took another one 14 DPO in the evening and line was a bit darker. Took a digital 15 DPO that said pregnant 1-2 weeks. Didnt take another test until I was 18 dpo and line was as faint as my 13/14dpo and same again for this morning’s 19dpo. I’m fairly sure I’m having a chemical pregnancy, I’m going to test again tonight as the only good positive I have received on a dye test has been in the evening. Can you tell me how long after a chemical it would no longer show on a test and when will I start bleeding?

Thanks :(