Possible chemical pregnancy

I'm only 12 dpo rn I started testing at 9dpo

9dpo stark negative on 2 different test

10dpo I had a faint positive at night

11dpo I only had one type of test but used 2 and they steadily got darker through the day

12dpo I got just a hint of a line at 2am and by 9am my tests were negative

Could I really have only caught the beginning of a pregnancy for a little over a day?