Missed birth control & sex

Hi guys, so i have a little situation i’m hoping you all can help me on! My pharmacist forgot to call in my birth control for me the first day i was supposed to start my new pack. which was this past monday. i did not take a pill monday. tuesday i doubles up. i took my first pill around 1:30 in the afternoon and 11:00 at night. i woke up around 5am and threw up just once because my stomach is super sensitive and the nausea really irritates me every time i double up. the following day which was yesterday (Wednesday) i had unprotected sex around 12:00 am technically this morning and the guy did not finish at all. what are my chances of becoming pregnant due to these circumstances? i took my pill after the sex and i feel fine today. should i take plan b? let me know your thoughts!