Unprotected sex

Ugh okay I’m 13 weeks pp and just had my first period last week. Well last night we had sex for the first time again and he took off the condom. We were thinking to use plan b but I exclusively breast feed and don’t have enough breast milk stored and we read it’s safe to take but may decrease milk supply for a couple days. Has anyone tried plan b while breastfeeding

Also he pulled out he did not finish inside of me so I’m not too worried but 🤷🏼‍♀️