Can you get pregnant if you have been using the pill correctly every day but forgot to take it one night and took it in the morning instead and had sex the day after your period ended?

Its difficult to say. There is always a possibility of pregnancy especially if you experienced break through ovulation while on the BCP or the dosage isn't strong enough for you. In this case pregnancy can occur.

If you have been on BCP for over 3 months you should be ok as you took the pill as soon as you remembered. I think you will be ok but your period may be a day early or late due to missing one pill. If your period doesn't arrive, take your pills as normal but do a pregnancy test. If you get a positive, STOP taking the BCP and see your doctor asap.