birth control questions

so i just got on birth control about 2 weeks ago and i was told by the doctor that the effects of it would start after 1 week. i’ve never used the pill before and this is my first time so i’m a little cautious and am thinking about taking a plan B since me and my boyfriend have been taking advantage of being able to prevent pregnancy.

-can someone share their experience?

-has anyone takin a plan b while on BC, does it affect the responses?

-i haven’t had any symptoms so far and i know there probably will be, what is something i should expect?

i will probably add more questions later, thanks to anyone who answers.