chance of pregnancy? help

my boyfriend came in me, i am on birth control and took a plan b for reasoning that i take my birth control late sometimes. my doctor put me on an antibiotic to get rid of an ear infection. i know i can’t have unprotected sex but is my birth control still going to work or is the plan b going to work even if i’m on the antibiotic, i wouldn’t be worried if my boyfriend didn’t cum in me but he did.