Missed mini pill/ implantation bleeding

Hey girls, Iv been taking the mini pill cerelle since September 2020, and my periods have completely stopped (yay🥳) me and my fiancé had intercourse on Sunday the 31st (to be exact) 2 days after that I started getting some diarrhoea due to coronavirus (which I never knew I had) I missed 1-2 which isn’t unlikely for me and nothing ever happens but 8 days after I had sex I had some spotting when I wiped, I just assumed I was getting a period and put a pad on, when I checked later there was barley anything in the pad. I had some light cramping but it went away after an hour or so. The spotting lasted 1 day or less. I read somewhere that implantation bleeding can happen 8-9 after conception and the timing just added up perfectly. As I am on birth control I am not trying for a baby atm just wondering if anyone knows if it is breakthrough bleeding or implantation? I just find it weird as Iv NEVER had breakthrough bleeding even after I’d missed pills.