post partum experiences taking plan b

hi all. my son turned 2 months old yesterday and my husband and i had sex for the first time post partum today. my husband pulled out, but we did not use any other form of contraception. i have PCOS, i am pumping + formula feeding, and my period hasn't come back yet. while i might be overthinking it, i am getting worried about the chance of pregnancy... therefore, has anyone had experience using plan b while a few weeks post partum? i have never used it before and i am worried about the side effects. i have never had issues with birth control, so hopefully i will be okay with plan b too? fyi going forward we will be using the pull out method + condoms and/or birth control 🤦‍♀️