Am I pregnant or over analysing?

So in March this year I got the implant, got it taken out in November for many factors but started the combined pill the same night to keep chances of pregnancy very low, but now my boyfriend and I have decided that we wouldn't exactly "ttc" but not try to prevent it either? So I've came off the pill and from some research i've done because of how unclear of my tracking has been for months for obvious reasons, I apparently had unprocted sex on the 2nd day of my "fertile window" (22nd December) but i'm not sure on how closely accurate this is as according to eve my period is now due in 10 days so I'm aware of how paranoid I probably am being but I genuinely think I may have concieved but is it too late in my "cycle" to have done so considering the above?