Pregnant and birth control. ..

I just found out that I'm pregnant, but I on birth control for over a year, I don't know what happened I always take the pill at the same time. I wasn't trying to convince at all. What can happen because i was taking the pill till today I want my baby to be fine. At the end of the day is a blessing. . And I don't know how I'm going to tell my SO either. .... can the baby have problems because I was on bc?