It can not be said that whether any chance of ectopic or not.
But yes there is definetly very less chance of pregnancy
it self if you have taken unwanted 72. But if failure happen than you can not say whether it is going to be normal or ectopic pregnancy
Both are different things and not much correlated. Yes theoraticaly there is more chance of ectopic pregnancy while on tablets. But you just had one hormonal tablets so there is further more less chance.
So don't worry.
Wait for your menses and if not comes than do urine pregnancy test and confirm.
Yes it can delay your menses or even menses can be irregular while you take unwanted 72.
You can bleed within 3 to 4 days for 1 day due to unwanted 72 and than again you may have your period. This may happen or may not. It depends on day of you cycle and levels of hormones (Chemicals) in your body. Mostly you will get your period. And there is less chance of ectopic than normal couple having unprotected sex without unwanted 72.